**5.2 Aerosolisation of anticancer drugs in pulmonary metastases**

**5.2.1 Interleukin-2**  The characteristics of clinical trials of inhaled interleukin-2 are summarized in Table 1.

Interleukin-2 (Il-2) was initially administered intravenously to treat patients with melanomas and renal cell carcinoma with some good results (Rosenberg et al., 1994). However, severe toxicity limits its intravenous administration (Mitani et al., 1992). It was logical, therefore, to evaluate IL-2 delivered *via* the airways. It was the first drug delivered *via* this route to be tested in a clinical trial for treating lung metastases (Huland et al., 1994). Patients with pulmonary metastases of renal-cell carcinoma were given IL-2 together with low doses of IL-2 injected subcutaneously (10% of total IL-2 dose) and systemic subcutaneous interferon alpha (IFN alpha). Toxicity was low, grade II toxicity occurred in only one patient who suffered bronchospasms. The pulmonary metastases did not increase during treatment. One of the 15 patients treated showed a complete response, 8 had partial responses, and the lung disease of 6 was stable. Surprisingly, 3 of 7 patients had partial responses of non-pulmonary metastases and one was stabilized. The mean survival time was 19.1 months, whereas the mean survival time of patients with renal carcinoma metastases is usually 9.9 months.

Inhaled natural IL-2 alone was also assessed in a phase I study on 16 patients, including 14 with pulmonary metastases of renal cell carcinomas and 2 non small cell lung cancers (Lorenz et al., 1996). Treatment was initially delivered once a day and progressively increased to reach 5 times a day over 43 days. Aerosol particles had an MMAD of about 2.3 µm. Treatment was relatively safe. Coughs were one of the most common adverse side effects and one patient fractured a rib, but no systemic toxicity was reported. The effect on lung function was mild to moderate. IL-2 was not detected in the blood with the low dose, but increased within 2 to 6 hours with the high dose. The pulmonary metastases of 3 patients went into complete regression, but 2 of them died from non-pulmonary metastases. The safety and efficacy of inhaled IL-2 was evaluated in a study on 7 patients with pulmonary metastases of renal carcinomas (Nakamoto et al., 1997). The drug was aerosolised with an ultrasonic nebuliser and delivered over 10 minutes for 5 days a week. Treatment was associated with subcutaneous injections of interferon alpha. One patient stopped the treatment before three months because his overall health deteriorated. The disease of two of the remaining 6 became stable, 3 had partial responses and the disease of one patient with cystic renal disease progressed. One patient developed severe toxicity, pulmonary fibrosis appearing within 4 months and treatment was stopped. His metastases grew dramatically and he died 6 months after treatment cessation.

The safety of inhaled IL-2 led Huland et al. to perform a clinical trial on a large cohort (Huland et al., 1999a). The 116 patients with pulmonary metastases of renal carcinoma included this 6-year study were given high doses of aerosolised IL-2, either alone (11%),

promising results, no clinical trial to assess the efficacy of inhaled 5-FU has been published,

To the best of our knowledge, no clinical trial has assessed the efficacy of inhaled nonsteroidal anti-inflammatory drugs for treating cancer patients, although aerosolised celecoxib plus i.v. chemotherapeutic agents showed good results in preclinical studies.

The characteristics of clinical trials of inhaled interleukin-2 are summarized in Table 1. Interleukin-2 (Il-2) was initially administered intravenously to treat patients with melanomas and renal cell carcinoma with some good results (Rosenberg et al., 1994). However, severe toxicity limits its intravenous administration (Mitani et al., 1992). It was logical, therefore, to evaluate IL-2 delivered *via* the airways. It was the first drug delivered *via* this route to be tested in a clinical trial for treating lung metastases (Huland et al., 1994). Patients with pulmonary metastases of renal-cell carcinoma were given IL-2 together with low doses of IL-2 injected subcutaneously (10% of total IL-2 dose) and systemic subcutaneous interferon alpha (IFN alpha). Toxicity was low, grade II toxicity occurred in only one patient who suffered bronchospasms. The pulmonary metastases did not increase during treatment. One of the 15 patients treated showed a complete response, 8 had partial responses, and the lung disease of 6 was stable. Surprisingly, 3 of 7 patients had partial responses of non-pulmonary metastases and one was stabilized. The mean survival time was 19.1 months, whereas the mean survival time of patients with renal carcinoma

Inhaled natural IL-2 alone was also assessed in a phase I study on 16 patients, including 14 with pulmonary metastases of renal cell carcinomas and 2 non small cell lung cancers (Lorenz et al., 1996). Treatment was initially delivered once a day and progressively increased to reach 5 times a day over 43 days. Aerosol particles had an MMAD of about 2.3 µm. Treatment was relatively safe. Coughs were one of the most common adverse side effects and one patient fractured a rib, but no systemic toxicity was reported. The effect on lung function was mild to moderate. IL-2 was not detected in the blood with the low dose, but increased within 2 to 6 hours with the high dose. The pulmonary metastases of 3 patients went into complete regression, but 2 of them died from non-pulmonary metastases. The safety and efficacy of inhaled IL-2 was evaluated in a study on 7 patients with pulmonary metastases of renal carcinomas (Nakamoto et al., 1997). The drug was aerosolised with an ultrasonic nebuliser and delivered over 10 minutes for 5 days a week. Treatment was associated with subcutaneous injections of interferon alpha. One patient stopped the treatment before three months because his overall health deteriorated. The disease of two of the remaining 6 became stable, 3 had partial responses and the disease of one patient with cystic renal disease progressed. One patient developed severe toxicity, pulmonary fibrosis appearing within 4 months and treatment was stopped. His metastases

The safety of inhaled IL-2 led Huland et al. to perform a clinical trial on a large cohort (Huland et al., 1999a). The 116 patients with pulmonary metastases of renal carcinoma included this 6-year study were given high doses of aerosolised IL-2, either alone (11%),

probably because i.v. injected 5-FU is not indicated for treating lung cancer.

**5.2 Aerosolisation of anticancer drugs in pulmonary metastases** 

grew dramatically and he died 6 months after treatment cessation.

**5.1.5 Non-steroidal anti-inflammatory drugs** 

**5.2.1 Interleukin-2** 

metastases is usually 9.9 months.

with a low dose given subcutaneously IL-2 (33%), or with low-dose systemic IL-2 and interferon-alpha (56%). The overall response rate was 16% for IL-2 alone, 49% for IL-2 plus subcutaneous (s.c.) IL-2, and 35% for IL-2 plus s.c. IL-2 and interferon. The median overall response was 9.6 months. The pulmonary metastases of 15% of patients progressed and those of 55% were stabilized. The authors identified risk factors of poor response in patients treated with inhaled IL-2 (Huland et al., 1999b). Of the 116 patients given inhaled IL-2 (natural or recombinant), 86 had a poor response and at least one of the following risk factors: 1 metastatic location (86%), interval between diagnosis and treatment of <12 months (62%), weight loss prior to therapy (41%), and ECOG (Eastern Cooperative Oncology Group) performance status ≥2 (13%). However, the response rate, including long-term stabilization, was 27 to 57% in patients with these risk factors. Inhaled IL-2 should be proposed for all renal cancer patients with pulmonary metastases. However, patient with multiple nodules and who are tired may have reduced lung deposition of inhaled treatment. Another clinical trial was conducted on 40 patients with progressive pulmonary metastases of a renal cell carcinoma. They were treated with inhaled IL-2 3 times a day for a total dose of 18 million units (MU) plus a low dose of systemic IL-2 (Merimsky et al., 2004). The dose was reduced for one patient because of a cough and dyspnea. The dose was increased to 36 MU for seven patients whose disease progressed. The response rate was poorer than in previous studies supervised by Huland et al. Only one of the 40 patients had a partial response, but the disease of 22 patients was stabilized. The median time to progression was 8.7 months. Toxicity was low including cough, weakness, dyspnea, fever and abdominal pain. The efficacy and safety of inhaled IL-2 were also assessed in a retrospective study on 51 patients with pulmonary metastases of renal cell carcinoma (Esteban-González et al., 2007). The patients were given 3 cycles of 36 MU per day for 5 days per week for 12 weeks. Toxicity was low, always grade 1 or 2. Cough and fatigue were the most common problems. The overall objective response rate was 13.7%. The median progression-free survival time was 8.6 months and the overall survival time was 23 months. Inhaled IL-2 seemed to have an effect but it was not compared to a control group. A retrospective study compared 94 patients with metastases of renal carcinoma treated with inhaled IL-2 to 103 patients treated with systemic IL-2 (Huland et al., 2003). The toxicity in the two groups was radically different. Cough was observed in the inhaled IL-2 group and fever, fatigue, skin lesion in systemic IL-2 group. The 1-, 2- and 3-year survival rates were estimated to be 47%, 28% and 23% for inhaled IL-2 and 26%, 10% and 1% for the systemic IL-2 group. The hazard ratio for inhaled IL-2 was 0.435. The death risk of patients treated with inhaled IL-2 was decreased by 44%.

The largest clinical trial with a drug delivered *via* the pulmonary route to treat lung cancer was the study conducting by Atzpodien et al. (Atzpodien et al., 2006). The 379 patients with metastases of renal cell carcinoma were randomly assigned to group I (143 patients) or group II (236 patients). The group I patients in arm A were given subcutaneous IL-2, subcutaneous interferon-α plus 13-cis-retinoic acid; those in arm B were given the same treatment as arm A plus inhaled IL-2. The patients in group II were assigned to arm C (arm A plus intraveinous 5-FU) or arm D (arm A plus oral capecitabine). The 13-cis-retinoic acid used in this study is a regulator of cell differentiation that has been reported to enhance the antitumor effect of IL-2/IFN-α on renal cell carcinoma metastases (Atzpodien et al, 1995). Patients with pulmonary metastases were preferentially assigned to group I. Arm B patients were given systemic IL-2 and IFN- plus inhaled IL-2 on days 1 to 5 of weeks 2 and 3 and

The Airways: A Promising Route for the Pulmonary Delivery of Anticancer Agents 69

weeks 5 to 8 with a pneumatic nebuliser producing 3 µm particles. A cycle was considered to be 8 weeks and patients were given 3 courses. Sixty patients (15.8%) (arm A: 14%; arm B: 9.2%; arm C: 21.6%; arm D: 15%) did not complete treatment due to disease progression before the first evaluation (2.9%), intolerance (8.7%), death during therapy (1.6%), patients' wish (2.1%), and non-compliance (0.5%). The endpoints were overall survival, progressionfree survival and objective response to treatment. In arm A, 8 patients (10%) had a complete response and 15 patients (19%) had a partial response, 28 (36%) had stable disease and the disease of 27 (35%) progressed despite treatment. The overall objective response rate was 29% (95% CI 19, 40). In arm B, 8 patients (12%) had a complete response, 12 (19%) a partial response, 17 (26%) had stable disease, and the disease of 28 (43%) progressed. The overall objective response rate was 31% (95% CI 20, 44). The patients in arms C and D had similar results. Progression-free survival was 5 months in arm A, 4 months in arm B, 0 month in arm C and 4 months in arm D with no statistical difference between them. The overall survival time was 22 months in arm A, 18 months in arm B, 18 months in arm C, and 16 months in arm D with no statistical difference. All four treatments were moderately well tolerated with equal toxicity for each arm (more than 5% of grade III/IV toxicity). No respiratory toxicity was reported in arm B with inhaled IL-2. The treatment based on s.c. IL-2, s.c. IFN and oral 13-cis-retinoic acid was probably too toxic for the advantages of inhaled IL-2 to be detected. Clinical trials associating an oral tyrosine kinase inhibitor like sorafenib with inhaled IL-2 might be interesting. A study on 10 patients reported asthma in response

to inhaled IL-2 (Loppow et al., 2007), but only one patient had to stop treatment.

reducing the number of treatments.

**5.2.2 Monoclonal antibodies and tyrosine kinase inhibitor** 

**5.2.3 Granulocyte Macrophage Colony Stimulating Factor (GM-CSF)** 

kinase inhibitors for treating lung cancer patients.

Skubitz et al. demonstrated that interleukin-2 encapsulated in liposomes could be delivered by aerosol to patients with pulmonary metastases (Skubitz et al., 2000). They gave 9 patients liposomes containing IL-2 or placebo with a jet nebuliser and a standard compressor. The IL-2 treatment was inhaled for about 20 minutes 3 times a day. No significant toxicity was observed and inhalation was well tolerated. Further studies are expected. However, it is hard to see the clinical advantage of inhaled liposomal IL-2 considering the impressive results of the free form, unless it could improve IL-2 resident time in the airways, so

To the best of our knowledge, no clinical trials have tested inhaled antibodies or tyrosine

GM-CSF was first assessed in a dose escalation study on 7 patients with pulmonary metastases (2 patients with osteosarcoma, 2 with melanoma, 1 with leiomyosarcoma, 1 with renal cell carcinoma and 1 with Ewing's sarcoma) (Anderson et al., 1999). They were given GM-CSF aerosolised with a pneumatic nebuliser. One was not treated due to rapid disease progression. The remaining 6 patients were given the drug twice a day for one week, and treatment was stopped for one week. The starting dose was 60 µg. The dose was increased to determine dose-limiting toxicity. Those given the high dose showed a minor increase in their white blood cell count that was not statistically different from their white blood cell count before treatment. Lung function was stable except in one patient with osteosarcoma whose FVC increased. No toxicity was described. Although it was a dose escalation study, treatment response was reported. Of the six patients who completed study, the disease of 4


Table 1. Main characteristics of clinical trials assessing inhaled interleukin-2. PFS: progression-free survival, OS: overall survival, CR: complete response, PR: partial response, SD: stable disease.

Grade 2 (7%) Bronchospasm in

Mild to moderate decrement of lung function

1 patient with pulmonary fibrosis

1 patient

Cough

**rate** 

1 CR 8 PR 6 SD

1 CR 1 PR 6 SD

3 PR 2 SD




IL-2

IL-2

1 PR 22 SD

Arm A: 12% CR 19% PR 26% SD Arm B: 10% CR 19% PR 36% SD

CR/PR/SD: 13.7%

Grade 3 (16%) CR/PR/SD:

cough CR/PR/SD:

cough, weakness, dyspnea, fever and abdominal

Equal toxicity for each arm (more than 5% of grade III/IV toxicity). No respiratory toxicity was reported in arm B

Grade 1 and 2 exclusively

progression-free survival, OS: overall survival, CR: complete response, PR: partial response,

Table 1. Main characteristics of clinical trials assessing inhaled interleukin-2. PFS:

pain

**Outcome** 

NA

NA

OS= 19,1 months

PFS= 9.6 months

OS= 11.8 months

Inhaled IL-2

1-year survival : 47% 2- year survival: 28% 3-year survival: 23% Systemic IL-2 1-year survival : 26% 2- year survival: 10% 3-year survival: 1%

PFS=8.7 months

Arm A : PFS=5 months OS= 22 months Arm B : PFS= 4 months OS= 18 months

PFS=8.6 months OS=23 months

 **Drugs Patients Toxicity Response** 

15 patients with RCC

14 patients with RCC 2 patients with NSCLC

7 patients with RCC

116 patients with RCC

94 patients with inhaled IL-2 and 103 patients with systemic IL-

40 patients with RCC

379 patients with RCC

with RCC

2

Inhaled IL-2 51 patients

**Huland et al. 1994** 

**Lorenz et al. 1996** 

**Nakamoto et al. 1997** 

**Huland et al. 1999** 

**Huland et al. 2003** 

**Merimsky et al. 2003** 

**Atzpodien et al. 2006** 

**Esteban-González et al. 2007** 

SD: stable disease.

Inhaled IL2 + low dose systemic IL-2 + systemic IFN

Inhaled IL-2 alone

Inhaled IL-2 and s.c. IFN

Inhaled IL-2 either alone or with low dose s.c. IL-2 or with low-dose s.c. IL-2 and IFN

Inhaled IL-2 vs systemic IL-2

Inhaled IL-2 and low dose systemic IL-2

Arm A : and systemic IL-2 and 13-cisretinoic acid Arm B: Arm A and Inhaled IL-2

weeks 5 to 8 with a pneumatic nebuliser producing 3 µm particles. A cycle was considered to be 8 weeks and patients were given 3 courses. Sixty patients (15.8%) (arm A: 14%; arm B: 9.2%; arm C: 21.6%; arm D: 15%) did not complete treatment due to disease progression before the first evaluation (2.9%), intolerance (8.7%), death during therapy (1.6%), patients' wish (2.1%), and non-compliance (0.5%). The endpoints were overall survival, progressionfree survival and objective response to treatment. In arm A, 8 patients (10%) had a complete response and 15 patients (19%) had a partial response, 28 (36%) had stable disease and the disease of 27 (35%) progressed despite treatment. The overall objective response rate was 29% (95% CI 19, 40). In arm B, 8 patients (12%) had a complete response, 12 (19%) a partial response, 17 (26%) had stable disease, and the disease of 28 (43%) progressed. The overall objective response rate was 31% (95% CI 20, 44). The patients in arms C and D had similar results. Progression-free survival was 5 months in arm A, 4 months in arm B, 0 month in arm C and 4 months in arm D with no statistical difference between them. The overall survival time was 22 months in arm A, 18 months in arm B, 18 months in arm C, and 16 months in arm D with no statistical difference. All four treatments were moderately well tolerated with equal toxicity for each arm (more than 5% of grade III/IV toxicity). No respiratory toxicity was reported in arm B with inhaled IL-2. The treatment based on s.c. IL-2, s.c. IFN and oral 13-cis-retinoic acid was probably too toxic for the advantages of inhaled IL-2 to be detected. Clinical trials associating an oral tyrosine kinase inhibitor like sorafenib with inhaled IL-2 might be interesting. A study on 10 patients reported asthma in response to inhaled IL-2 (Loppow et al., 2007), but only one patient had to stop treatment.

Skubitz et al. demonstrated that interleukin-2 encapsulated in liposomes could be delivered by aerosol to patients with pulmonary metastases (Skubitz et al., 2000). They gave 9 patients liposomes containing IL-2 or placebo with a jet nebuliser and a standard compressor. The IL-2 treatment was inhaled for about 20 minutes 3 times a day. No significant toxicity was observed and inhalation was well tolerated. Further studies are expected. However, it is hard to see the clinical advantage of inhaled liposomal IL-2 considering the impressive results of the free form, unless it could improve IL-2 resident time in the airways, so reducing the number of treatments.

#### **5.2.2 Monoclonal antibodies and tyrosine kinase inhibitor**

To the best of our knowledge, no clinical trials have tested inhaled antibodies or tyrosine kinase inhibitors for treating lung cancer patients.

#### **5.2.3 Granulocyte Macrophage Colony Stimulating Factor (GM-CSF)**

GM-CSF was first assessed in a dose escalation study on 7 patients with pulmonary metastases (2 patients with osteosarcoma, 2 with melanoma, 1 with leiomyosarcoma, 1 with renal cell carcinoma and 1 with Ewing's sarcoma) (Anderson et al., 1999). They were given GM-CSF aerosolised with a pneumatic nebuliser. One was not treated due to rapid disease progression. The remaining 6 patients were given the drug twice a day for one week, and treatment was stopped for one week. The starting dose was 60 µg. The dose was increased to determine dose-limiting toxicity. Those given the high dose showed a minor increase in their white blood cell count that was not statistically different from their white blood cell count before treatment. Lung function was stable except in one patient with osteosarcoma whose FVC increased. No toxicity was described. Although it was a dose escalation study, treatment response was reported. Of the six patients who completed study, the disease of 4

The Airways: A Promising Route for the Pulmonary Delivery of Anticancer Agents 71

decrease breathlessness because there are morphine receptors in the lungs. The safety and pharmacology of aerosolised-morphine have been evaluated in cancer patients with

A safety trial conducted on 50 cancer patients with dyspnea revealed no major adverse reactions, such as respiratory distress or vomiting (Tanaka et al., 1999). The 20 mg dose of morphine was delivered with an ultrasonic nebuliser. Dyspnea was measured using a visual analog scale based on the subjective quantification of breathlessness by the patient.

Morphine 6 glycuronide (M6G) is an active metabolite of morphine. The pharmacokinetics of inhaled M6G were analysed on 10 healthy volunteers (Penson et al., 2002). M6G was delivered as an intravenous bolus (2 mg), subcutaneously (2 mg) or by inhalation (4 mg). The bioavailability of M6G was 102% after s.c. delivery and 6% after airways delivery compared to intravenous route. The peak of M6G in the blood appeared from 30 minutes to 2 h after s.c. delivery and from 1.2 to 8 hours after airways delivery. A previous study found that the bioavailability of nebulised morphine was 17%, suggesting that little passed into the blood (Chrubasik et al., 1988). A recent study by Krajnik et al. compared two methods of morphine nebulisation (Krajnik et al, 2009). Morphine, at a dose of 5 mg, was given to 10 breathless cancer patients with a nebuliser producing 2-5 µm or 0.5-2 µm particle droplets. The nebuliser producing the larger particles resulted in more metabolite being released into the blood, but a longer procedure was needed to deliver the 5 mg dose and the maximum plasma concentration of the metabolite occurred later. No toxicity was observed. A clinical

The published pharmacokinetic studies on morphine and its metabolite suggest that little

The safety profile and poor passage into the blood led to clinical trials to analyse the efficacy of inhaled morphine. Quigley el al. treated 9 cancer patients suffering from breathlessness with M6G in a phase I/II study (Quigley et al., 2002). They were given a single dose of 5 mg, 10 mg, or 20 mg M6G. Treatment was well tolerated. Pharmacokinetic analysis showed a blood peak at 2 hours for all doses with a blood concentration proportional to the dose. The patient status based on visual analog scale of breathlessness and dyspnea (Borg score) was significantly improved, with no difference between doses. The inhalation of a derivative of morphine, hydromorphone, was also evaluated in cancer patients (Coyne et al., 2002). These 32 breathless patients inhaled hydromorphone and were assessed at baseline, 5 minutes and 60 minutes after nebulisation. The patients assessed their change as the same, worse, or improved. Most of them (26; 81%) reported improved breathing and 6 (9%) found no change. Oxygen saturation was improved from 94.6% at baseline to 96.8% at 5 minutes and

The above results should be interpreted with caution because there was no control group (aerosolised placebo or i.v. opioids). A few years ago we performed a trial with inhaled

Nebulised morphine produced a significant 10% decrease in dyspnea.

trial comparing the efficacy of the two devices is required.

dyspnea. **5.3.1.1 Safety** 

**5.3.1.2 Pharmacokinetics** 

passes into the blood.

96.7% at 60 minutes. 5.3.1.3.2 Controlled trials

5.3.1.3.1 Uncontrolled trials

**5.3.1.3 Efficacy** 

stabilized for 9 months, 1 had a partial response and 1 had a complete response (patient with Ewing's sarcoma). The authors suggest that the low GM-CSF concentration into the bloodstream after airways delivery may be attributed to GM-CSF sequestration into the lungs by immune effectors. This therapy was given to 45 other patients (40 with pulmonary metastases) to better evaluate the toxicity of inhaled GM-CSF (Rao et al., 2003). They were given nebulised GM-CSF (250 µg) twice a day for 1 week followed by a 1 week rest. Moderate toxicity was observed in 18 patients. The disease of 24 patients was stabilized or partially responded (8 of 13 with a sarcoma, 6 of 14 with melanoma, and 5 of 12 with renal cell carcinoma). The efficacy of aerosolised GM-CSF might be due to stimulation of an antitumor immune response because one patient with pulmonary metastases of melanoma had a 10-fold increase in specific cytotoxic T lymphocytes resulting in a partial response. The authors suggested that there was a dose-dependent response to the treatment and conducted a third dose escalation study with doses higher than in previous trials (Markovic et al., 2008). Only patients with pulmonary metastases of melanomas were included because the authors postulated that there could be an antitumor auto-immunization against the melanoma, as suggested by increase in melanoma-specific lymphocyte T in previous study. Aerosolised GM-CSF was delivered with a pneumatic nebuliser twice daily on days 1 to 7 and 15 to 21 in a 28-day cycle. Doses ranged from 500 to 2000 µg. The author considered aerosolised GM-CSF to be well tolerated.because only 3 of the 40 patients had severe toxicity, including grade 4 dyspnea in 1 patient given 2000 µg and 1 patient given 1750 µg, and grade 3 fatigue in 1 patient given 1000 µg. There were increases in melanoma-specific cytotoxic T lymphocytes in 9 patients (1 given 500 µg, 1 given 750 µg, 2 given 1500 µg, 1 given 1750 µg, and 4 given 2000 µg). Although the data are descriptive, the authors reported that one patient on 2000 µg had a partial response and the disease of 6 became stable. None of the GM-CSF doses used induced antitumor immunity in the majority of patients. Further studies are needed to determine the extent of the antitumor immunity induced by aersosolised GM-CSF in melanoma. A recent clinical trial treated 43 adults and children with lung relapses of osteosarcoma with inhaled GM-CSF. They were given 2 cycles of inhaled GM-CSF, then the tumour nodules were surgically removed. The patients were then given 12 cycles of inhaled GM-CSF (Arndt et al., 2010). Treatment was given 5 days per week every 2 weeks and the dose range was from 250 µg to 1750 µg. The Fas and Fas ligand were assayed in the removed nodules to assess the immunomodulatory effect of GM-CSF. Nine patients had grade 3 respiratory toxicity, including 5 patients on 1750 µg. Thirty seven patients suffered relapses. The median free survival time was 4.3 months and the overall survival rates were 63.1% at 2 years and 35.4% at 3 years. GM-CSF was found to have no immunomodulatory effect, and this potential property of GM-CSF remains controversial.

#### **5.3 Aerosols in palliative cancer care**

Breathlessness is a serious problem for cancer patients in palliative care because of the discomfort it causes. Drugs are usually given systemically to relieve this discomfort, but this is invasive and often requires hospitalization.

#### **5.3.1 Morphine and other opiod analgesics**

The opiate analgesic morphine is widely used and is given orally, intravenously or subcutaneously to cancer patients to relieve pain. The effect of morphine on breathlessness was suggested more than 20 years ago (Bruera et al. 1990) and reported in a systematic review in 2002 (Jennings et al., 2002). Delivering morphine *via* the pulmonary route might decrease breathlessness because there are morphine receptors in the lungs. The safety and pharmacology of aerosolised-morphine have been evaluated in cancer patients with dyspnea.

### **5.3.1.1 Safety**

70 Advances in Cancer Therapy

stabilized for 9 months, 1 had a partial response and 1 had a complete response (patient with Ewing's sarcoma). The authors suggest that the low GM-CSF concentration into the bloodstream after airways delivery may be attributed to GM-CSF sequestration into the lungs by immune effectors. This therapy was given to 45 other patients (40 with pulmonary metastases) to better evaluate the toxicity of inhaled GM-CSF (Rao et al., 2003). They were given nebulised GM-CSF (250 µg) twice a day for 1 week followed by a 1 week rest. Moderate toxicity was observed in 18 patients. The disease of 24 patients was stabilized or partially responded (8 of 13 with a sarcoma, 6 of 14 with melanoma, and 5 of 12 with renal cell carcinoma). The efficacy of aerosolised GM-CSF might be due to stimulation of an antitumor immune response because one patient with pulmonary metastases of melanoma had a 10-fold increase in specific cytotoxic T lymphocytes resulting in a partial response. The authors suggested that there was a dose-dependent response to the treatment and conducted a third dose escalation study with doses higher than in previous trials (Markovic et al., 2008). Only patients with pulmonary metastases of melanomas were included because the authors postulated that there could be an antitumor auto-immunization against the melanoma, as suggested by increase in melanoma-specific lymphocyte T in previous study. Aerosolised GM-CSF was delivered with a pneumatic nebuliser twice daily on days 1 to 7 and 15 to 21 in a 28-day cycle. Doses ranged from 500 to 2000 µg. The author considered aerosolised GM-CSF to be well tolerated.because only 3 of the 40 patients had severe toxicity, including grade 4 dyspnea in 1 patient given 2000 µg and 1 patient given 1750 µg, and grade 3 fatigue in 1 patient given 1000 µg. There were increases in melanoma-specific cytotoxic T lymphocytes in 9 patients (1 given 500 µg, 1 given 750 µg, 2 given 1500 µg, 1 given 1750 µg, and 4 given 2000 µg). Although the data are descriptive, the authors reported that one patient on 2000 µg had a partial response and the disease of 6 became stable. None of the GM-CSF doses used induced antitumor immunity in the majority of patients. Further studies are needed to determine the extent of the antitumor immunity induced by aersosolised GM-CSF in melanoma. A recent clinical trial treated 43 adults and children with lung relapses of osteosarcoma with inhaled GM-CSF. They were given 2 cycles of inhaled GM-CSF, then the tumour nodules were surgically removed. The patients were then given 12 cycles of inhaled GM-CSF (Arndt et al., 2010). Treatment was given 5 days per week every 2 weeks and the dose range was from 250 µg to 1750 µg. The Fas and Fas ligand were assayed in the removed nodules to assess the immunomodulatory effect of GM-CSF. Nine patients had grade 3 respiratory toxicity, including 5 patients on 1750 µg. Thirty seven patients suffered relapses. The median free survival time was 4.3 months and the overall survival rates were 63.1% at 2 years and 35.4% at 3 years. GM-CSF was found to have no immunomodulatory effect, and this potential property of GM-CSF remains controversial.

Breathlessness is a serious problem for cancer patients in palliative care because of the discomfort it causes. Drugs are usually given systemically to relieve this discomfort, but this

The opiate analgesic morphine is widely used and is given orally, intravenously or subcutaneously to cancer patients to relieve pain. The effect of morphine on breathlessness was suggested more than 20 years ago (Bruera et al. 1990) and reported in a systematic review in 2002 (Jennings et al., 2002). Delivering morphine *via* the pulmonary route might

**5.3 Aerosols in palliative cancer care** 

is invasive and often requires hospitalization.

**5.3.1 Morphine and other opiod analgesics** 

A safety trial conducted on 50 cancer patients with dyspnea revealed no major adverse reactions, such as respiratory distress or vomiting (Tanaka et al., 1999). The 20 mg dose of morphine was delivered with an ultrasonic nebuliser. Dyspnea was measured using a visual analog scale based on the subjective quantification of breathlessness by the patient. Nebulised morphine produced a significant 10% decrease in dyspnea.

#### **5.3.1.2 Pharmacokinetics**

Morphine 6 glycuronide (M6G) is an active metabolite of morphine. The pharmacokinetics of inhaled M6G were analysed on 10 healthy volunteers (Penson et al., 2002). M6G was delivered as an intravenous bolus (2 mg), subcutaneously (2 mg) or by inhalation (4 mg). The bioavailability of M6G was 102% after s.c. delivery and 6% after airways delivery compared to intravenous route. The peak of M6G in the blood appeared from 30 minutes to 2 h after s.c. delivery and from 1.2 to 8 hours after airways delivery. A previous study found that the bioavailability of nebulised morphine was 17%, suggesting that little passed into the blood (Chrubasik et al., 1988). A recent study by Krajnik et al. compared two methods of morphine nebulisation (Krajnik et al, 2009). Morphine, at a dose of 5 mg, was given to 10 breathless cancer patients with a nebuliser producing 2-5 µm or 0.5-2 µm particle droplets. The nebuliser producing the larger particles resulted in more metabolite being released into the blood, but a longer procedure was needed to deliver the 5 mg dose and the maximum plasma concentration of the metabolite occurred later. No toxicity was observed. A clinical trial comparing the efficacy of the two devices is required.

The published pharmacokinetic studies on morphine and its metabolite suggest that little passes into the blood.

#### **5.3.1.3 Efficacy**

#### 5.3.1.3.1 Uncontrolled trials

The safety profile and poor passage into the blood led to clinical trials to analyse the efficacy of inhaled morphine. Quigley el al. treated 9 cancer patients suffering from breathlessness with M6G in a phase I/II study (Quigley et al., 2002). They were given a single dose of 5 mg, 10 mg, or 20 mg M6G. Treatment was well tolerated. Pharmacokinetic analysis showed a blood peak at 2 hours for all doses with a blood concentration proportional to the dose. The patient status based on visual analog scale of breathlessness and dyspnea (Borg score) was significantly improved, with no difference between doses. The inhalation of a derivative of morphine, hydromorphone, was also evaluated in cancer patients (Coyne et al., 2002). These 32 breathless patients inhaled hydromorphone and were assessed at baseline, 5 minutes and 60 minutes after nebulisation. The patients assessed their change as the same, worse, or improved. Most of them (26; 81%) reported improved breathing and 6 (9%) found no change. Oxygen saturation was improved from 94.6% at baseline to 96.8% at 5 minutes and 96.7% at 60 minutes.

#### 5.3.1.3.2 Controlled trials

The above results should be interpreted with caution because there was no control group (aerosolised placebo or i.v. opioids). A few years ago we performed a trial with inhaled

The Airways: A Promising Route for the Pulmonary Delivery of Anticancer Agents 73

significance (Stone et al., 2002). Another study that included placebo group confirmed that inhaled furosemide had little effect on the breathlessness of 15 cancer patients (Wilcock et al., 2008). They assessed the patients' perception of breathing before and 60 minutes after treatment; they found no improvement in either group. There were small decreases in FEV1

The chemoprevention of lung cancer with aerosolised drugs was first tested in animals. Budesonide, an inhaled steroid, inhibited the formation of lung tumour by over 80% (Wattenberg et al., 1997). Squamous cell carcinoma in hamsters was reduced by 50% with inhaled difluoromethylornitine and 60% with and inhaled 5-FU (Wattenberg et al., 2004). The results of clinical trials of the chemopreventive effects of inhaled steroid have been equivocal. Lam et al. suggested that budesonide had no effect on bronchial dysplastic lesions and did not prevent new lesions forming in 112 smokers (Lam et al., 2004). In contrast, fluticasone delivered by aerosol gave promising results, with significantly fewer treated patients with increasing numbers of nodules than in the placebo group (Van den Berg et al., 2008). A clinical trial in which 11 subjects with lung metaplasia or dysplasia were given aerosolized vitamin A found complete or partial responses in 56% of cases (Kohlhäufl

Further studies are needed to determine whether inhaled steroid and vitamin A really do

Others aerosolised agents such as pioglitazone (an antidiabetic agent), polyphenons E (a mixture of polyphenons) and bexarotene (a retinoid X receptor (RXR) agonist) had promising results in animal studies (Fu et al. 2009, 2011, Yan et al., 2007, Zhang et al. 2011).

Most of the preclinical studies have shown that aerosolisation preserves anti-cancer properties of a large amount of agents. Administration through the pulmonary route of anticancer drugs is well tolerated in animal models. Lung deposition is better following airways than systemic delivery. Moreover, blood passage is often lower when anti-cancer agents are administered through the airways. To date, the clinical studies of inhaled anticancer agents such as cisplatin, campthotecin, 5-fluoro-uracile, have demonstrated the safety and the pharmacokinetic advantages of airways administration in cancer patients. Moreover, antitumor responses have been observed including complete remission with inhaled interleukin-2 in renal cell carcinoma patients or with inhaled doxorubicin in lung cancer patients. However, studies were constructed with a small number of patients, the histological patterns were mostly heterogeneous with primary and secondary lung tumour mixed in the same trial and different devices or dosage were used to evaluate response to the same agent. Thus, it is difficult to bring conclusions on the real efficacy of anti-cancer agents administered through the airways, but significant effects are obvious. Despite promising results of inhaled anticancer drugs, the aerosol delivery of opioid or furosemide in palliative cancer patients was not convincing. Chemoprevention of lung cancer with inhaled agents is interesting, but further studies are needed to validate this approach. It would be valuable to systematically integrate aerosol metrology and pharmacokinetic analysis with preclinical studies in order to improve drug deposition at the target site in the respiratory tract, and define the formulation that enables drugs to be retained in the lungs.

and vital capacity after nebulised normal saline but not after nebulised furosemide.

**5.4 Chemoprevention of lung cancer by aerosolisation** 

et al., 2002)

have chemopreventive effects.

**6. Perspectives and conclusion** 

morphine (20 mg) or normal saline in 10 cancer patients (Grimbert et al., 2004). The patients were given both treatments over 48 hours, separated by a wash-out period. Dyspnea, respiratory rate and oxygen saturation were assessed on a visual analog scale before and after treatment. The scores improved after both treatments, but respiratory rate and oxygen saturation did not change, indicating no specific drug response. We postulated that the improved comfort was due to a nebulisation-dependent humidification of the airways or a placebo response. Our results differ from those of Coyne et al., who described an improved perception of breathing, respiratory rate and oxygen saturation following treatment with nebulised fentanyl citrate (Coyne et al., 2002). This difference may be due to a great variation in the oxygen saturation measured and the subjective dyspnea measurement.

Bruera et al. compared the effects of nebulised morphine and subcutaneous morphine on 11 cancer patients suffering from breathlessness (Bruera et al., 2005). On day 1 they were given nebulised morphine plus a subcutaneous placebo, or nebulised placebo plus subcutaneous morphine. The treatments were reversed on day 2. Both treatments were very well tolerated. The score of the group given morphine subcutaneously decreased significantly from 5 to 3 on a visual analog scale, and that of the nebulised drug group decreased from 4 to 2. However, only 11 patients were studied and the visual analog scale fluctuated during the subcutaneous morphine treatment. A more recent study compared the effects of nebulised hydromorphone, intravenous hydromorphone, and nebulised normal saline on twenty patients (Charles et al., 2008). Patients needing treatment for breathlessness were randomly given 5 mg of nebulised hydromorphone, a systemic breakthrough dose of hydromorphone, or 3 ml of nebulised saline on three different occasions. A placebo given by another route was administrated. The primary goal of a decrease in the visual analog scale within 10 minutes was not reached. There were significant decreases over a longer period but no difference between treatments.

Thus, these studies with a placebo control group have not demonstrated any difference between nebulised opioid and placebo. However both treatments seemed to significantly improve the patients' perception of breathing, which may be attributed to a placebo effect or improved airway humidity.

#### **5.3.2 Furosemide**

Inhaled furosemide was used with some success to treat breathlessness asthma patients and healthy volunteers whose breathlessness was induced (Bianco et al., 1989, Nishino et al., 2000).

This finding led to inhaled furosemide being evaluated in cancer patients. A group of three cancer patients reported improved dyspnea when given nebulised furosemide (20 mg) (Shimoyama et al., 2002). Nebulisation of a bronchodilator before giving inhaled furosemide had no effect and the authors excluded a placebo effect. A study on 15 cancer patients suffering from breathlessness assessed the effect of ultrasonically nebulised furosemide (20 mg) (Kohara et al., 2003). Cancer dyspnea was measured with a brief self-rating scale of 12 items. Most patients (n=12; 80%) reported significant improvements in their cancer dyspnea and anxiety. Their heart rates, respiratory rates and oxygen saturation were not improved. The improved dyspnea might have been due to a placebo effect or improved airway humidity, as observed in inhaled morphine studies. A controlled trial on 7 cancer patients treated with inhaled normal saline or furosemide (20 mg) found that the scores of the visual analog scale were better after saline than after furosemide, but without statistical significance (Stone et al., 2002). Another study that included placebo group confirmed that inhaled furosemide had little effect on the breathlessness of 15 cancer patients (Wilcock et al., 2008). They assessed the patients' perception of breathing before and 60 minutes after treatment; they found no improvement in either group. There were small decreases in FEV1 and vital capacity after nebulised normal saline but not after nebulised furosemide.

### **5.4 Chemoprevention of lung cancer by aerosolisation**

72 Advances in Cancer Therapy

morphine (20 mg) or normal saline in 10 cancer patients (Grimbert et al., 2004). The patients were given both treatments over 48 hours, separated by a wash-out period. Dyspnea, respiratory rate and oxygen saturation were assessed on a visual analog scale before and after treatment. The scores improved after both treatments, but respiratory rate and oxygen saturation did not change, indicating no specific drug response. We postulated that the improved comfort was due to a nebulisation-dependent humidification of the airways or a placebo response. Our results differ from those of Coyne et al., who described an improved perception of breathing, respiratory rate and oxygen saturation following treatment with nebulised fentanyl citrate (Coyne et al., 2002). This difference may be due to a great variation in the oxygen saturation measured and the subjective dyspnea measurement. Bruera et al. compared the effects of nebulised morphine and subcutaneous morphine on 11 cancer patients suffering from breathlessness (Bruera et al., 2005). On day 1 they were given nebulised morphine plus a subcutaneous placebo, or nebulised placebo plus subcutaneous morphine. The treatments were reversed on day 2. Both treatments were very well tolerated. The score of the group given morphine subcutaneously decreased significantly from 5 to 3 on a visual analog scale, and that of the nebulised drug group decreased from 4 to 2. However, only 11 patients were studied and the visual analog scale fluctuated during the subcutaneous morphine treatment. A more recent study compared the effects of nebulised hydromorphone, intravenous hydromorphone, and nebulised normal saline on twenty patients (Charles et al., 2008). Patients needing treatment for breathlessness were randomly given 5 mg of nebulised hydromorphone, a systemic breakthrough dose of hydromorphone, or 3 ml of nebulised saline on three different occasions. A placebo given by another route was administrated. The primary goal of a decrease in the visual analog scale within 10 minutes was not reached. There were significant decreases over a longer period but no

Thus, these studies with a placebo control group have not demonstrated any difference between nebulised opioid and placebo. However both treatments seemed to significantly improve the patients' perception of breathing, which may be attributed to a placebo effect or

Inhaled furosemide was used with some success to treat breathlessness asthma patients and healthy volunteers whose breathlessness was induced (Bianco et al., 1989, Nishino et al.,

This finding led to inhaled furosemide being evaluated in cancer patients. A group of three cancer patients reported improved dyspnea when given nebulised furosemide (20 mg) (Shimoyama et al., 2002). Nebulisation of a bronchodilator before giving inhaled furosemide had no effect and the authors excluded a placebo effect. A study on 15 cancer patients suffering from breathlessness assessed the effect of ultrasonically nebulised furosemide (20 mg) (Kohara et al., 2003). Cancer dyspnea was measured with a brief self-rating scale of 12 items. Most patients (n=12; 80%) reported significant improvements in their cancer dyspnea and anxiety. Their heart rates, respiratory rates and oxygen saturation were not improved. The improved dyspnea might have been due to a placebo effect or improved airway humidity, as observed in inhaled morphine studies. A controlled trial on 7 cancer patients treated with inhaled normal saline or furosemide (20 mg) found that the scores of the visual analog scale were better after saline than after furosemide, but without statistical

difference between treatments.

improved airway humidity.

**5.3.2 Furosemide** 

2000).

The chemoprevention of lung cancer with aerosolised drugs was first tested in animals. Budesonide, an inhaled steroid, inhibited the formation of lung tumour by over 80% (Wattenberg et al., 1997). Squamous cell carcinoma in hamsters was reduced by 50% with inhaled difluoromethylornitine and 60% with and inhaled 5-FU (Wattenberg et al., 2004).

The results of clinical trials of the chemopreventive effects of inhaled steroid have been equivocal. Lam et al. suggested that budesonide had no effect on bronchial dysplastic lesions and did not prevent new lesions forming in 112 smokers (Lam et al., 2004). In contrast, fluticasone delivered by aerosol gave promising results, with significantly fewer treated patients with increasing numbers of nodules than in the placebo group (Van den Berg et al., 2008). A clinical trial in which 11 subjects with lung metaplasia or dysplasia were given aerosolized vitamin A found complete or partial responses in 56% of cases (Kohlhäufl et al., 2002)

Further studies are needed to determine whether inhaled steroid and vitamin A really do have chemopreventive effects.

Others aerosolised agents such as pioglitazone (an antidiabetic agent), polyphenons E (a mixture of polyphenons) and bexarotene (a retinoid X receptor (RXR) agonist) had promising results in animal studies (Fu et al. 2009, 2011, Yan et al., 2007, Zhang et al. 2011).
