Randomized phase II trial of cisplatin with mitomycin or doxorubicin for malignant mesothelioma by the Cancer and Leukemia Group B

Current chemotherapy strategies in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is an aggressive malignancy with a 5-year survival rate of ~10%. Since most patients present with irresectable disease, the vast majority is treated with chemotherapy. The only registered therapy for MPM is platinum-pemetrexed doublet therapy, although only up to half of patients have clinical benefit from this palliative treatment. Of the anti-angiogenesis agents, only bevacizumab and nintedanib have shown activity with platinum-pemetrexed doublet therapy. Other anti-angiogenesis agents like thalidomide did not prolong (progression free) survival or response rate. Eventually, all patients will get a recurrence and no active second line therapy has been identified to date. The clinical benefit of (switch) maintenance therapy after first line treatment and combination strategies of different chemotherapies with angiogenesis inhibitors are currently under investigation. The major challenges are finding optimal treatment combinations and to select the adequate treatment for an individual patient. This review focusses on the current standard of chemotherapy and new systemic therapy strategies under investigation.

Surgery Followed by Intracavitary plus Systemic Chemotherapy in Malignant Pleural Mesothelioma

Aims and background

Malignant mesothelioma is associated with a median survival of 4 to 12 months. Data from the literature indicate that single modality treatment (surgery or intrapleural and/or systemic chemotherapy) does not significantly affect survival.

Methods

We therefore evaluated a combined approach consisting of surgery (pleurectomy + diaphragmatic or pericardial resection), intrapleural chemotherapy with cisplatin (100 mg/m2) and cytarabine (1,000 mg/m2) for 4 h immediately after pleurectomy, and systemic chemotherapy consisting of epirubicin (60 mg/m2) and mitomycin-C (10 mg/m2) day 1 every 4 weeks for 4 cycles.

Results

Twenty patients were enrolled in the study and were evaluable. Thirteen cases had residual gross disease after pleurectomy and 7 patients only minimal disease. Median time to disease progression was 7.4 months, and median survival was 11.5 months (range, 2-25+). No treatment-related death have been observed. Side effects after intracavitary chemotherapy included renal toxicity, anaemia and pain. Myelosuppression and alopecia were recorded during systemic chemotherapy.

Conclusions

The results of the study indicate that the schedule is feasible, with encouraging results in terms of survival for patients with minimal residual disease after surgery.

Response to Chemotherapy of Brain Metastases from Malignant Pleural Mesothelioma

Brain metastases represent an uncommon complication in malignant pleural mesothelioma. A 55-year-old male suffering from malignant mesothelioma and pretreated with intracavitary chemotherapy and radiotherapy was submitted to systemic chemotherapy including lomustine, carboplatin, vinorelbine, fluorouracil and folates after diagnosis of bilateral cerebral deposits. The patient had an impressive response to chemotherapy, with complete regression of related symptoms. This case report represents the first on response to chemotherapy of brain metastases from mesothelioma. It points out that chemotherapy should be further explored in this subset of patients.

Oxaliplatin and Raltitrexed in the Treatment of Inoperable Malignant Pleural Mesothelioma: Results of a Pilot Study

Aims and Background

The treatment of inoperable malignant pleural mesothelioma is a challenge for the oncologist. Available chemotherapy regimens achieve poor results, therefore new agents or combinations are needed. In a phase I study, the combination of oxaliplatin and raltitrexed was shown to be active against malignant pleural mesothelioma. We herein report the results of a pilot study about the treatment of this disease.

Methods

From April 1999 to June 2000, we enrolled 11 chemotherapy-naïve patients with inoperable malignant pleural mesothelioma suitable to receive the following combination chemotherapy: raltitrexed, 3 mg/m2 iv, and oxaliplatin, 130 mg/m2, as a 2-hr infusion every 3 weeks.

Results

Four partial responses, 1 regression of disease (objective response rate, 45%; 95% Cl, 15.6-74.4%), 4 stable diseases and 2 progressions of disease were observed. An improvement in disease-related symptoms was recorded in all responders and in 2 patients with stable disease. Toxicity was mild, with no toxic-related death and only 1 episode of grade 4 neurotoxicity.

Conclusions

We consider the combination promising and worthy of further studies.

Chemotherapy treatment in malignant pleural mesothelioma: a difficult history

Malignant pleural mesothelioma (MPM) is a rare neoplasm that typically arises from mesothelial surfaces of the pleural cavity. Despite treatment improvements, it carries a dismal prognosis. The majority of patients either have unresectable disease or are not candidates for surgery due to medical comorbidities or old age. For such patients, chemotherapy (CT) represents the gold-standard treatment. To date, combination CT with cisplatin plus pemetrexed represents the most widely used regimen in first-line setting for patients with unresectable MPM. Other first-line options are currently available, including the use of raltitrexed instead of pemetrexed combined with platinum. In this review, we discuss the role of CT in MPM mainly focusing on the results of the trials conducted in first-line setting.

Effects of carbon ion beam alone or in combination with cisplatin on malignant mesothelioma cells in vitro

Malignant mesothelioma (MM) is extremely aggressive and a typical refractory cancer. In this study we investigated how effective on killing MM cells by carbon ion beam alone or in combination with cisplatin (CDDP) in vitro. Carbon ion beam (at the center of SOBP with 50 keV/µm of average LET) dose-independently suppressed MM cells MESO-1 and H226 cell viability and in combination with CDDP (25 μM) significantly enhanced its action. Relative biological effectiveness (RBE) values at 73 keV/μm and 13 keV/μm portion of carbon ion beam was estimated as 2.82-2.93 and 1.19-1.22 at D10 level relative to X-ray, respectively by using colony formation assay. Quantitative real time PCR analysis showed that expression of apoptosis-related BAX and autophagy-related Beclin1 and ATG7 was significantly enhanced by carbon ion beam alone or in combination with CDDP. Apoptosis analysis showed that caspase 3/7 activity and the percentage of apoptotic cells was dose-dependently increased after carbon ion beam and it was further increased when combined with CDDP. Spheroid formation ability of cancer stem like CD44+/CD26+ cells was significantly inhibited by carbon ion beam combined with CDDP. Besides, carbon ion beam combined with cisplatin significantly inhibited cell cycle progression (sub-G1 arrest) and induced more large number of γH2AX foci. In conclusion, carbon ion beam combined with CDDP has superior potential to kill MM cells including CSCs with enhanced apoptosis.

Novel systemic therapy against malignant pleural mesothelioma

Malignant pleural mesothelioma is an aggressive tumor of the pleura with an overall poor prognosis. Even with surgical resection, for which only a subset of patients are eligible, long term disease free survival is rare. Standard first-line systemic treatment consists of a platinum analog, an anti-metabolite, and sometimes anti-angiogenic therapy, but there is currently no well-established standard therapy for refractory or relapsed disease. This review focuses on efforts to develop improved systemic therapy for the treatment of malignant pleural mesothelioma (MPM) including cytotoxic systemic therapy, a variety of tyrosine kinase inhibitors and their downstream effector pathways, pharmacologic targeting of the epigenome, novel approaches to target proteins expressed on mesothelioma cells (such as mesothelin), arginine depletion therapy, and the emerging role of immunotherapy. Overall, these studies demonstrate the challenges of improving systemic therapy for MPM and highlight the need to develop therapeutic strategies to control this disease.

Validation of Progression-Free Survival as a Surrogate Endpoint for Overall Survival in Malignant Mesothelioma: Analysis of Cancer and Leukemia Group B and North Central Cancer Treatment Group (Alliance) Trials

PURPOSE

The aim of this study was to investigate whether progression-free survival (PFS) can be considered a surrogate endpoint for overall survival (OS) in malignant mesothelioma.

MATERIALS AND METHODS

Individual data were collected from 15 Cancer and Leukemia Group B (615 patients) and 2 North Central Cancer Treatment Group (101 patients) phase II trials. The effects of 5 risk factors for OS and PFS, including age, histology, performance status (PS), white blood cell count, and European Organisation for Research and Treatment of Cancer (EORTC) risk score, were used in the analysis. Individual-level surrogacy was assessed by Kendall's tau through a Clayton bivariate Copula survival (CBCS) model. Summary-level surrogacy was evaluated via the association between logarithms of the hazard ratio (log HR)-log HR_OS and log HR_PFS-measured in R² from a weighted least-square (WLS) regression model and the CBCS model.

RESULTS

The median PFS for all patients was 3.0 months (95% confidence interval [CI], 2.8-3.5 months) and the median OS was 7.2 months (95% CI, 6.5-8.0 months). Moderate correlations between PFS and OS were observed across all risk factors at the individual level, with Kendall's tau ranging from 0.46 to 0.47. The summary-level surrogacy varied among risk factors. The Copula R² ranged from 0.51 for PS to 0.78 for histology. The WLS R² ranged from 0.26 for EORTC and PS to 0.67 for age.

CONCLUSIONS

The analyses demonstrated low to moderate individual-level surrogacy between PFS and OS. At the summary level, the surrogacy between PFS and OS varied significantly across different risk factors. With a short postprogression survival and a moderate correlation between PFS and OS, there is no evidence that PFS is a valid surrogate endpoint for OS in malignant mesothelioma. The Oncologist 2017;22:189-198Implications for Practice: For better disease management and for more efficient clinical trial designs, it is important to know if progression-free survival (PFS) is a good surrogate endpoint for overall survival in malignant mesothelioma. With a relatively large database of 17 phase II trials and 716 patients from Cancer and Leukemia Group B and North Central Cancer Treatment Group, we conducted statistical analyses and found that there is no evidence to suggest that PFS is a valid surrogate endpoint for OS for malignant mesothelioma. Future research work is needed to find alternative surrogate endpoints for OS.

Prolonged response to pemetrexed-based chemotherapy in a patient with peritoneal mesothelioma: a case report and review of the literature

Peritoneal mesothelioma is a rare tumor typically presenting with ascites and associated with occupational asbestos exposure with a latency period of 20–40 years. Intensive multi-modality approach combining cytoreductive surgery, intraperitoneal chemotherapy and possibly radiotherapy can be considered, but otherwise the prognosis is rather poor. Palliative chemotherapy may be an option in these rare cases. However, no approved systemic treatment exists for peritoneal mesothelioma. We present here a patient with peritoneal mesothelioma who was treated with the combination of pemetrexed with cisplatin shortly after the failure of hyperthermic intraperitoneal chemotherapy. The patient experienced durable partial response to the treatment, resolution of ascites, and returned to his normal daily life activities. With the exception of palliative chemotherapy in case of patients in good condition, therapeutic options in patients with peritoneal mesothelioma are currently very limited. The combination of pemetrexed and cisplatin can lead to long-term control in selected patients.

Malignant pleural mesothelioma: current and future perspectives

Mesothelioma still remains an occupational related cancer with severe outcome. It is usually diagnosed at advanced stage since it does not demonstrate early symptoms. Several efforts have been made towards removing all materials inducing mesothelioma in the work setting and new work protection measures have been applied. Although we have new targeted treatments and radical surgery as arrows in the quiver, the type of mesothelioma and early diagnosis still remain the best treatment approach. Novel treatment modalities have been explored and several others are already on the way. In the current review we will present current data for mesothelioma and future perspectives.

Peritoneal mesothelioma: current status and future directions

Peritoneal mesothelioma is a rare malignancy where life expectancy with systemic chemotherapy remains poor. Most patients with this disease are diagnosed late with extensive peritoneal disease burden leading to nausea, pain, and abdominal distention as a result of ascites and a partial bowel obstruction. A newly proposed staging system comprising elements of the tumor burden measured by the peritoneal cancer index, abdominal nodal status, and extra-abdominal metastases has been demonstrated to reliably stratify patient outcomes based on staging subgroups after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. This new staging system may form the basis of selecting patients for radical surgery and improve survival outcomes.

Preclinical studies identify novel targeted pharmacological strategies for treatment of human malignant pleural mesothelioma

The incidence of human malignant pleural mesothelioma (hMPM) is still increasing worldwide. hMPM prognosis is poor even if the median survival time has been slightly improved after the introduction of the up-to-date chemotherapy. Nevertheless, large phase II/III trials support the combination of platinum derivatives and pemetrexed or raltitrexed, as preferred first-line schedule. Better understanding of the molecular machinery of hMPM will lead to the design and synthesis of novel compounds targeted against pathways identified as crucial for hMPM cell proliferation and spreading. Among them, several receptors tyrosine kinase show altered activity in subsets of hMPM. This observation suggests that these kinases might represent novel therapeutic targets in this chemotherapy-resistant disease. Over these foundations, several promising studies are ongoing at preclinical level and novel molecules are currently under evaluation as well. Yet, established tumour cell lines, used for decades to investigate the efficacy of anticancer agents, although still the main source of drug efficacy studies, after long-term cultures tend to biologically diverge from the original tumour, limiting the predictive potential of in vivo efficacy. Cancer stem cells (CSCs), a subpopulation of malignant cells capable of self-renewal and multilineage differentiation, are believed to play an essential role in cancer initiation, growth, metastasization and relapse, being responsible of chemo- and radiotherapy refractoriness. According to the current carcinogenesis theory, CSCs represent the tumour-initiating cell (TIC) fraction, the only clonogenic subpopulation able to originate a tumour mass. Consequently, the recently described isolation of TICs from hMPM, the proposed main pharmacological target for novel antitumoural drugs, may contribute to better dissect the biology and multidrug resistance pathways controlling hMPM growth.

First-line chemotherapy with liposomal doxorubicin plus cisplatin for patients with advanced malignant pleural mesothelioma: phase II trial

Background:

Chemotherapy based on platinum is the standard treatment for unresectable malignant pleural mesothelioma (MPM). Liposomal doxorubicin (LD) consists of pegylated phospholipid vesicles that encapsulate doxorubicin-enhancing liposome deposition in the tumour. We evaluated the toxicity profile and anti-tumour activity of cisplatin plus LD in untreated patients with MPM, as well as ^99mTc-LD distribution in MPM lesions after chemotherapy administration.

Methods:

A total of 38 patients with non-resectable MPM received LD 40 mg m⁻² and cisplatin 60 mg m⁻² every 21 days. Gamma camera images of ^99mTc-LD were acquired to evaluate LD accumulation in measurable tumour tissue. The study was registered in Clinical Trials (NCT00886028).

Results:

In all, 72% of patients were stage III and 28% were stage IV. Eighty four percent and 16% have high and low risk acording EORTC respectively. The median time to progression was 4.6 months (95% confidence interval (95% CI: 3.4–5.9 months), and median overall survival (OS) was 19.6 months (15.2–37.2 months). Patients that responded to chemotherapy treatment had better survival than patients who did not. Functional physical scales, dysnea, cough, and chest/arm pain demonstrated improvement. The accumulation ratio of LD in tumour and soft tissues vs liver was 0.78±0.16 and 0.29±0.09, respectively. After 1 h of administration, LD uptake in tumour tissue was higher than in soft tissue (P< 0.001).

Conclusion:

The combination of LD and cisplatin results in an active therapeutic regimen for unresectable MPM, with an acceptable toxicity profile and improvement in quality of life. ^99mTc-LD showed higher levels of tumour uptake as compared with surrounding tissues.

Combined chemotherapy with cytotoxic and targeted compounds for the management of human malignant pleural mesothelioma

Human malignant pleural mesothelioma (hMPM) is an aggressive asbestos-associated cancer, the incidence of which is increasing and which, despite progress in diagnosis and therapy, continues to have a poor prognosis. Asbestos fibers induce aberrant cell signaling, leading to proto-oncogene activation and chemoresistance. In this review, we discuss the evolution of pharmacological management of hMPM up to the most recent advances. Monotherapy with single cytotoxic drugs achieves modest objective response rates, seldom reaching 30%. However, combination regimens using novel drugs and standard molecules are showing gradually improving responses and clinical benefits. Phase II/III studies have identified pemetrexed, a multitarget folate pathway inhibitor in combination with platinum derivatives, and the cisplatin/gemcitabine association as front-line chemotherapy for hMPM. Detailed knowledge of molecular mechanisms of signal transduction and neoangiogenesis in hMPM should aid in the design and screening of other promising compounds such as more efficacious receptor tyrosine kinase inhibitors.

Two-stage operative cytoreduction and intraperitoneal chemotherapy for diffuse malignant peritoneal mesothelioma: Operative morbidity and mortality in phase I and II trials

AIMS

The standard of care for diffuse malignant peritoneal mesothelioma involves operative cytoreduction and intraperitoneal chemotherapy. Most centers favor aggressive operative cytoreduction, accepting high morbidity and mortality. In our trials, patients underwent less extensive cytoreduction followed by prolonged intraperitoneal chemotherapy. Patients underwent a second cytoreduction with heated intraperitoneal chemotherapy. We hypothesized this would result in lower operative morbidity and mortality with similar survival.

METHODS

Hospital records, discharge summaries, microbiology, radiography, and office records were retrospectively reviewed to supplement a prospective database. 30-day morbidity and mortality were categorized, and classified according to the Clavien methodology.

RESULTS

47 first and 39 second operations were performed with 13% and 26% morbidity, respectively. Mortality was 2%. Infections comprised 59% of the morbidity. Inclusive of both operations, formal peritonectomy was performed in 16% of patients, resection of isolated lesions in less than half, and only 19% had a visceral organs other than the spleen resected. At the completion of the protocol, only 3% of patients had visible intraperitoneal disease. The mean total length of stay for both operations combined was 16 ± 23 days. Overall median survival was 54.9 months, and median survival for the epithelioid subtype was 70.2 months.

CONCLUSIONS

A two-stage cytoreduction with intraperitoneal chemotherapy offers median survival comparable to one-stage protocols, with relatively low morbidity, mortality, visceral resections and length of stay despite two operations. This series supports that our protocol is a feasible and safe approach.

Management of malignant pleural mesothelioma

Malignant pleural mesothelioma is a rare neoplasm arising from the surface serosal cells of the pleural cavity. More than 80% of cases of malignant pleural mesothelioma have been attributed to asbestos exposure. In its natural course median survival is 4 to 12 months. If untreated most of patients die due to local complications of the disease. Surgery improves local control but is not sufficient as a single treatment modality. The recommended treatment strategy for a select group of patients is multimodal therapy that includes surgery, radiotherapy and chemotherapy.

Carboplatin plus pemetrexed as first-line treatment of patients with malignant pleural mesothelioma: a phase II study

INTRODUCTION

Malignant pleural mesothelioma (MPM) is a rapidly progressive tumor that is increasing in frequency worldwide. Treatment options are limited, and response to chemotherapy is poor. The aim of this phase II study was to evaluate the activity of the carboplatin/pemetrexed combination as first-line chemotherapy in patients with unresectable MPM.

PATIENTS AND METHODS

Chemotherapy-naive patients with histologically confirmed MPM and an Eastern Cooperative Oncology Group performance status of 0-2 were enrolled. Treatment consisted of pemetrexed 500 mg/m2 and carboplatin area under the concentration-time curve of 5 mg/mL/min, both administered on day 1 of a 21-day cycle. The treatment continued until 6 cycles were completed or until unacceptable toxicity or disease progression were observed.

RESULTS

A total of 62 patients were enrolled. Of these patients, 18 (29%) had a confirmed partial response, whereas the disease remained stable in 34 patients (54.9%) and progressed in 10 patients (16.1%). The median overall survival (OS) was estimated at 14 months (95% CI, 11.8-16.2 months), and the median time to progression was 7 months (95% CI, 5.8-8.2 months). The difference in median OS between the epithelial histologic subtype (16 months) and the sarcomatoid subtype (11 months) was statistically significant.

CONCLUSION

This study confirmed the activity of the carboplatin/ pemetrexed combination in the first-line treatment of patients with MPM. It is a viable option, especially in cases in which side effects are generally anticipated.

Malignant pleural mesothelioma: medical treatment update

Malignant pleural mesothelioma (MPM) is a disease usually unaffected by current therapeutic strategies, but for the majority of patients, the use of systemic chemotherapeutic drugs remains the only therapeutic option available. During the past 15-20 years, many phase II and a few phase III clinical trials have studied a large variety of drugs such as anthracyclines, alkylating agents, platinum compounds, taxanes, vinka alkaloids, and antifolates as single agents and in combination, with the aim to increase responses and survival. The combination of pemetrexed and cisplatin tested in the largest phase III randomized trial of malignant pleural mesothelioma ever conducted has become the current standard of care. New targeted therapeutic approaches with a variety of anti-growth factor drugs are currently undergoing investigation worldwide.

Recent advances in the treatment of malignant pleural mesothelioma

Malignant pleural mesothelioma clinically manifests after decades of initial exposure to etiologic agents, such as asbestos, and presents with nonspecific symptoms such as dyspnea, pain, or weight loss. In patients with limited, resectable disease, surgical therapy with extrapleural pneumonectomy or pleurectomy is recommended, although, it is unclear which approach is superior. Radiation has a limited role and is used primarily for palliation. The palliative efficacy of traditional chemotherapeutic agents and combination regimens is modest at best. The combination of cisplatin and pemetrexed, a novel multitargeted antifolate agent, is the approved "standard of care" for patients with unresectable malignant pleural mesothelioma. A number of molecularly targeted agents are currently under evaluation for mesothelioma such as the Histone deacetylase (HDAC) inhibitors that have demonstrated promising anticancer activity. Vorinostat, a small molecule inhibitor of HDAC, which targets select members of class I and II HDACs, has shown early evidence of activity and is currently being evaluated in a randomized study for patients who progress with standard therapy for advanced mesothelioma. It is hoped that the HDAC inhibitors and other novel targeted agents will pave the way for improved outcomes for patients with this disease.

Malignant peritoneal mesothelioma-Results from the International Expanded Access Program using pemetrexed alone or in combination with a platinum agent

AIM

Peritoneal mesothelioma (PM) has rarely been studied. The Expanded Access Program (EAP) provided access to 109 patients with PM.

METHODS

This was a nonrandomized, open-label study conducted in chemo-naïve or previously treated patients with PM not amenable to curative surgery. Patients received pemetrexed (PEM) 500 mg/m2 alone or with cisplatin (CIS) 75 mg/m2 or carboplatin (CARBO) AUC 5 every 21 days, supplemented with standard vitamin B(12), folate, and dexamethasone.

RESULTS

Response rates (95% CI) for PEM, PEM/CIS, and PEM/CARBO were 12.5% (3.5, 29.0), 20.0% (7.7, 38.6), and 24.1% (10.3, 43.5), respectively. Median survival for PEM was 10.3 months. One-year survival rates for PEM/CIS and PEM were 57.4% (95% CI: 10.3, 100) and 41.5% (95% CI: 4.6, 78.4), respectively, and were not available for PEM/CARBO. Anemia was the most common serious adverse event (6.4%). Neutropenia (34.6%) was the most frequent CTC grade 3 or 4 toxicity reported.

CONCLUDING STATEMENT

PEM with or without a platinum agent was both active and well tolerated in patients with peritoneal mesothelioma.

Pemetrexed plus cisplatin or pemetrexed plus carboplatin for chemonaïve patients with malignant pleural mesothelioma: results of the International Expanded Access Program

INTRODUCTION

Previously published results from a randomized phase III study of pemetrexed plus cisplatin in patients with malignant pleural mesothelioma (MPM) demonstrated a significant survival benefit and higher response rate compared with cisplatin. Although pemetrexed was under review by regulatory agencies, an International Expanded Access Program (EAP) provided more than 3000 mesothelioma patients with access to single-agent pemetrexed or pemetrexed in combination with cisplatin or carboplatin in 13 countries. This manuscript reports the safety and efficacy data from the nonrandomized open-label study in chemonaïve patients receiving pemetrexed plus platinum under the EAP.

METHODS

Patients with histologically confirmed MPM, not amenable to curative surgery, received pemetrexed 500 mg/m in combination with either cisplatin 75 mg/m or carboplatin AUC 5, once every 21 days with standard premedication. Efficacy data were recorded at the end of study participation.

RESULTS

A total of 1704 chemonaïve patients received pemetrexed plus cisplatin (n = 843) or pemetrexed plus carboplatin (n = 861) and were evaluated for safety. The efficacy evaluable population consisted of 745 patients in the pemetrexed plus cisplatin group and 752 patients in the pemetrexed plus carboplatin group for whom physician-reported tumor response was available. The pemetrexed plus cisplatin group demonstrated a response rate of 26.3% compared with 21.7% for the pemetrexed plus carboplatin group, with similar 1-year survival rates (63.1% versus 64.0%) and median time to progressive disease (7 months versus 6.9 months). The most common grade 3/4 hematologic toxicity was neutropenia in 23.9% of the pemetrexed plus cisplatin group and 36.1% of the pemetrexed plus carboplatin group.

CONCLUSION

This large EAP confirmed the activity of pemetrexed plus cisplatin and pemetrexed plus carboplatin in chemonaïve patients with MPM, demonstrating clinically similar time to progressive disease and 1-year survival rates.

The serine protease HtrA1 is a novel prognostic factor for human mesothelioma

AIMS

The objective of our study was to analyze the potential prognostic value of the expression of the serine protease HtrA1 and of EGFR in 70 malignant mesotheliomas.

MATERIALS & METHODS

Immunohistochemistry was used to determine the expression of HtrA1 and EGFR. Univariate and multivariate analyses were used to correlate expression of these molecular factors in combination with available clinicopathologic data to patient survival.

RESULTS

A positive, statistically significant relationship has been recorded between HtrA1 expression level and survival (p < 0.0001). By contrast, a negative relationship has been identified between EGFR expression and survival (p = 0.02). Moreover, extension of the tumor (T) and involvement of lymph nodes (N) advanced status (p = 0.001 and 0.002, respectively), as well as the sarcomatoid histotype (p = 0.005), correlated significantly with poor survival. Finally, by a multivariate Cox regression analysis, the only immunohistochemical parameter that resulted to influence overall survival was HtrA1 (p = 0.0001). Interestingly, the prognostic value of HtrA1 expression was completely independent from EGFR expression (p < 0.0001).

CONCLUSION

This is the first study of the relationship between HtrA1 expression and survival of mesothelioma patients. The data obtained strongly indicate the utilization of HtrA1 expression as a prognostic parameter for mesothelioma and suggest this serine protease as a possible molecular target for the treatment of malignant mesotheliomas.

Piroxicam and intracavitary platinum-based chemotherapy for the treatment of advanced mesothelioma in pets: preliminary observations

Malignant Mesothelioma is an uncommon and very aggressive tumor that accounts for 1% of all the deaths secondary to malignancy in humans. Interestingly, this neoplasm has been occasionally described in companion animals as well. Aim of this study was the preclinical evaluation of the combination of piroxicam with platinum-based intracavitary chemotherapy in pets. Three companion animals have been treated in a three years period with this combination. Diagnosis was obtained by ultrasonographic exam of the body cavities that evidenced thickening of the mesothelium. A surgical biopsy further substantiated the diagnosis. After drainage of the malignant effusion from the affected cavity, the patients received four cycles of intracavitary CDDP at the dose of 50 mg/m² every three weeks if dogs or four cycles of intracavitary carboplatin at the dose of 180 mg/m² (every 3 weeks) if cats, coupled with daily administration of piroxicam at the dose of 0.3 mg/kg. The therapy was able to arrest the effusion in all patients for variable remission times: one dog is still in remission after 3 years, one dog died of progressive disease after 8 months and one cat died due to progressive neoplastic growth after six months, when the patient developed a mesothelial cuirass. The combination showed remarkable efficacy at controlling the malignant effusion secondary to MM in our patients and warrants further investigations.

Current therapies for malignant pleural mesothelioma

Mesothelioma is a highly lethal tumor derived from mesothelial cells, and its global incidence is increasing because of widespread exposure of numerous individuals to asbestos in the last 50 years. Mesothelioma is largely untreatable with any of the therapeutic modalities. Recently, a novel multitargeted antifolate pemetrexed has shown promising activity against malignant pleural mesothelioma, producing response rates of up to 40% when used in combination with cisplatin. In a large phase III study, use of a combination of pemetrexed and cisplatin was associated with significantly improved survival time and with greater antitumor activity compared with cisplatin alone. This combination also gave a significant response rate of approximately 50% in patients with epithelioid malignant pleural mesothelioma. These clinical benefits of pemetrexed-cisplatin doublet have changed the perception of mesothelioma chemotherapy. Other combinations, including gemcitabine in combination with cisplatin, have also shown encouraging response rates. Prognosis depends on gender, clinical stage of the tumor, histological subtype, platelet count, leukocyte counts, and performance status. Radiotherapy can palliate mesothelioma patients with chest pain, and has been indicated to be of benefit for the prevention of malignant seeding along the tract of a chest tube or needle biopsy. Trimodality treatment using extrapleural pneumonectomy, radiation and chemotherapy has shown promising therapeutic value. The development of chemotherapeutic regimens and the favorable outcomes of trimodality have led to new combined modality trials. In Japan, multicenter national trials against mesothelioma will begin in the near future.

Efficacy and safety of first- or second-line irinotecan, cisplatin, and mitomycin in mesothelioma

BACKGROUND

Malignant pleural mesothelioma (MPM) is a rapidly progressive lethal tumor. Treatment options remain limited and the outcome in recurrent disease is poor.

METHODS

A Phase II open-label noncomparative study was conducted to assess the safety and efficacy of the triplet combination irinotecan, cisplatin, and mitomycin-C (IPM) chemotherapy in untreated patients and in those with previous exposure to chemotherapy.

RESULTS

In 62 patients an objective response rate of 25% was observed. In the first-line setting progression-free survival measured 6.4 months (95% confidence interval [CI]: 4.5-7.3) and overall survival was 10.8 months (95% CI: 7.9-13.7). In the second-line setting progression-free survival was 7.3 months (95% CI: 3.4-11.2) and overall survival was also 7.3 months (95% CI: 4.8-9.8). Psychosocial well-being improved during chemotherapy and the main toxicity observed was neutropenia (40%).

CONCLUSIONS

IPM appeared to have a reasonable response rate with an acceptable toxicity profile in the first- and second-line treatment of MPM.

A retrospective analysis of malignant pleural mesothelioma patients treated either with chemotherapy or best supportive care between 1990 and 2005 A single institution experience

The aim of this study was to investigate the efficacy and safety profile of chemotherapy (CT) compared to best supportive care (BSC) in patients with histopathologically confirmed diffuse malignant pleural mesothelioma (DMPM). A total of 161 patients between 1990 and 2004 treated either with CT (109 patients) or BSC (52 patients) depending on patients choice were evaluated in this analyses. Chemotherapy protocols included a combination of cisplatin, mitomycin C and recombinant interferon alpha 2a (CM-In), or cisplatin, mitomycin C and ifosfamide (CMI), or cisplatin and gemcitabine (CG). We found a significant difference in the median survivals of the patients with CT compared to BSC, 11.3 months versus 8.0. Objective response rate was 28/109 (25.7%) with 3.7% of complete response rate. Stable disease rate was 39/109 (35.8%). There was a significant difference between median survivals of patients with objective response (17 months) and median survivals of patients with progressive diseases (6 months) and also with stable diseases (16 months). There was a significant difference between the stable disease and the progressive disease. Stages 3 and 4 patients of epithelial cell type having received chemotherapy live longer than those not having received chemotherapy (12 months versus 4). There was no significant difference between the survivals of the different chemotherapy regimens. The toxicity with CT regimens were mild and well-tolerated. We conclude that CT prolongs survival compared to BSC in patients with DMPM. Survivals of patients with objective response prolong considerably with CT compared BSC. We observed that stages 3 and 4 patients with epithelial cell type got benefit from CT. Especially, of epithelial cell type stages 1 and 2 should receive multimodal treatment.

Piroxicam and cisplatin in a mouse model of peritoneal mesothelioma

PURPOSE

The aim of the present study was to evaluate the effects of piroxicam, a widely used nonsteroidal anti-inflammatory drug, alone and in combination with cisplatin (CDDP), on cell growth of mesothelioma cells.

EXPERIMENTAL DESIGN

Cell proliferation, cell cycle analysis, and microarray technology were done on MSTO-211H and NCI-H2452 cells treated with piroxicam. Moreover, the effects of piroxicam and CDDP on tumor growth and survival of mouse xenograft models of mesothelioma were determined.

RESULTS

Piroxicam treatment of MSTO-211H and NCI-H2452 cells resulted in a significant inhibition of proliferation. Cell cycle analysis revealed that there was an increase in the rate of apoptosis in MSTO-211H cells and an increase in the cells accumulating in G2-M in NCI-H2452. Moreover, a marked tumor growth inhibition and an extended survival of mice treated with a combination of piroxicam and CDDP in MSTO-211H cell-induced peritoneal mesotheliomas was observed. Last, GeneChip array analysis of MSTO-211H mesothelioma cell line revealed that piroxicam treatment caused up-regulation of metabolic pathway-associated genes and down-regulation of genes related to RNA processing apparatus. Of note, epidermal growth factor receptor, one of the new biological targets of chemotherapy for mesothelioma, was down-regulated and HtrA1, a serine protease recently shown to be an endogenous mediator of CDDP cytotoxicity, was up-regulated following piroxicam treatment both in vitro and in vivo.

CONCLUSION

These data suggest that piroxicam sensitizes mesothelioma cells to CDDP-induced cytotoxicity by modulating the expression of several target genes. Therefore, piroxicam in combination with CDDP might potentially be useful in the treatment of patients with mesothelioma.

Efficacy of a combination of pemetrexed and multiple redo-surgery in an 11-year-old girl with a recurrent multifocal abdominal mesothelioma

We report the case of an 11-year-old girl with a recurrent progressive locally advanced abdominal mesothelioma. First, there was an incomplete surgical resection without any complementary chemotherapy, followed by a slow progression of the disease. Three years later, after two macroscopically complete surgical resections of peritoneal and ovarian tumors, she failed to respond to treatment with gemcitabin-carboplatin and gemcitabin-cisplatin, and developed splenic tumors and large multicystic hepatic tumors. She was then treated with pemetrexed. The schedule of chemotherapy was pemetrexed 400 mg intravenously plus cisplatin 60 mg once every 3 weeks associated with folic acid and vitamin B12. The tumor reduction was evaluated with positron emission tomography scan and tomodensitometry every three courses. Chemotherapy tolerance was good apart from a grade III neutropenia at the second course, a fever of unknown origin at the fifth course and a grade III thrombocytopenia at the sixth course. As tolerance and clinical responses were good, pemetrexed posology was increased up to 10%. After six courses, hepatic and splenic lesion tumors were initially diminished and then stablilized. Thus, a surgical resection was attempted: a first surgery followed by a second one 3 days later allowed completion of a difficult left hepatectomy, and resection of the hilum and splenic tumors. Fourteen months after the surgery, the girl remained in partial remission with stable disease. So far, pemetrexed associated with cisplatin revealed a good tolerance and promising results regarding its antitumoral efficacy in a progressive metastatic abdominal mesothelioma in childhood.

Phase II study of mitomycin-C, adriamycin, cisplatin (MAP) and Bleomycin-CCNU in patients with advanced cancer of the anal canal: An eastern cooperative oncology group study E7282

Metastatic anal cancer is a rare disease in the Western hemisphere and current treatment modalities are not effective. In this study, patients with advanced epithelial cancer of the anal canal received MAP followed by Bleomycin and CCNU upon progression of disease. Twelve out of twenty eligible patients had a partial response 60%, (95% CI {36% -81%}). No complete responses were observed. The median survival was 15 months (95% CI {6-20} months). The median time to progression or death was 8 months (95% CI {4-9 months}). Toxicities were moderate and tolerable with routine supportive care; there were 2 cases of grade 3 vomiting, 2 cases of respiratory distress (one grade 1 and one grade 3), one case each of grade 3 leg cramps and cardiac arrhythmia. Of particular note were 7 cases of grade 3 hematologic toxicity. Two patients had grade 4 leukopenia and thrombocytopenia, respectively, that resolved without sequelae. The combination therapy of MAP followed by Bleomycin and CCNU for patients with advanced anal cancer, not amenable to radiotherapy or surgery, results in a moderate objective response but with moderate toxicities. This regimen and sequence is worthy of further study especially in combination with colony stimulating factors, however, its tolerability may be most applicable for patients who have had minimal prior therapy.

Divided dose of cisplatin combined with gemcitabine in malignant mesothelioma

Malignant mesothelioma is a rare but notoriously chemoresistant tumor. An impressive activity of gemcitabine and cisplatin combination in malignant mesothelioma has been shown. However, the hematological toxicity and nephrotoxicity related to this regimen affect the patient's life negatively. The aim of this study is to investigate the efficacy and toxicity of divided dose of cisplatin combined with gemcitabine in chemo-naïve patients with malignant mesothelioma. Twenty-six eligible patients with malignant mesothelioma were enrolled onto the study. Cisplatin 35 mg/m(2) and gemcitabine 800 mg/m(2) were administered on days 1 and 8 as intravenous infusion in a 3-week cycle, up to maximum 6 cycles. Response and toxicity evaluations were performed in 26 patients. Male-female ratio was 11/15 with a mean age of 50.5 years (37-70). Locations of tumor were pleura in 16 patients, and peritoneum in 10 patients. All patients had epitheloid subtype of malignant mesothelioma. The partial response and stable disease were observed in 6 patients (23.1%) and in 13 patients (50%), respectively, with an overall tumor control rate of 73.1%. Seven patients (26.9%) had progressive disease. Median time to disease progression and survival were 4 and 19.5 months, respectively. Grade 3 nausea and vomiting were observed in one patient (3.8%), grade 4 neutropenia developed in one patient (3.8%) and grades 3-4 thrombocytopenia and nephrotoxicity did not develop. There was no treatment related death. Divided dose of cisplatin combined with gemcitabine, at the current dosage and schedule, appears to be an active regimen in chemotherapy-naïve patients with malignant mesothelioma, and well-tolerated.

The cancer and leukemia group B respiratory committee

The Cancer and Leukemia Group B Respiratory Committee has a 30-year track record of clinical investigation in patients with small-cell lung cancer and non-small-cell lung cancer (NSCLC) and mesothelioma. The most widely recognized contributions of the Committee include the early confirmation of the role of concurrent chemoradiotherapy in LD-SCLC, the effect of combination chemotherapy followed by radiation in stage III NSCLC, the introduction of third-generation agents into concurrent chemoradiation for stage III disease, the prospective demonstration of the benefit of treating older (70 years old) and poorer performance status (performance status = 2) patients with first-line combinations for stage IV disease, and the development of the "Herndon prognostic index" to normalize patient characteristics and outcomes in sequential phase II trials of new agents in patients with mesothelioma. Many other contributions have also emerged from the Committee's clinical trials and correlative science programs. We look forward to making additional critical contributions during future decades of Cancer and Leukemia Group B Respiratory Committee research.

Sequential chemotherapy with cisplatin/gemcitabine (CG) followed by mitoxantrone/methotrexate/mitomycin (MMM) in patients with malignant pleural mesothelioma

PURPOSE

We performed a multicenter phase II trial to evaluate the impact on the activity, efficacy, symptom control and safety of using two active regimens in a sequential schedule (cisplatin/gemcitabine followed by mitoxantrone/methotrexate/mitomycin) as first-line chemotherapy for unresectable malignant pleural mesothelioma (MPM).

PATIENTS AND METHODS

A total of 54 patients received cisplatin 75 mg/m(2) on day 1 and gemcitabine 1,200 mg/m(2) on days 1 and 8, every 3 weeks for four courses (CG regimen) followed by mitoxantrone 10 mg/m(2) on day 1, methotrexate 35 mg/m(2) on day 1 and mitomycin 7 mg/m(2) on day 1, every 3 weeks with mitomycin in alternate cycles for four courses (MMM regimen).

RESULTS

We observed 3 complete responses (CRs) (5.6%) and 13 partial responses (PRs) (24.0%), with an overall response rate (ORR) of 29.6% (95% confidence interval, 17-42%), 33 stable disease (SD) (61.1%) and 5 progressive disease (PD) (9.2%). Median time to progression (TTP) was 9.5 months (range, 2-23). Median overall survival (OS) was 13 months (range, 3-33); 1-year survival rate was 63%. The treatment produced a good symptom control, with an improvement during chemotherapy in dyspnea and pain in 52.9 and 48.3% of patients, respectively. The major toxicity observed was hematological. Grades 3-4 NCI-CTC v 2.0 toxicity with the CG regimen included: neutropenia (11.1%), anemia (1.9%), thrombocytopenia (7.4%), vomiting (11.1%) and with the MMM regimen: neutropenia (35.2%), anemia (5.5%), thrombocytopenia (7.4%) and stomatitis (1.9%).

CONCLUSION

This phase II study with the sequential approach of two active regimens showed a good disease control in MPM, with symptom improvement and only mild toxicity.

Pemetrexed in thoracic cancer

Both lung cancer and mesothelioma are malignancies with increasing incidence, and both are primarily due to inhalation of an external carcinogen. The occurence of both diseases is expected to rise worldwide, although a stabilisation and/or decrease may be anticipated in some developed countries. There are other common similarities to both cancers, including the median age of their patients, the advanced stage at presentation, the outcome and the treatments given. This review focuses on the available evidence of a novel antifolate agent, pemetrexed, in the treatment of both of these thoracic malignancies. Current status, persisting controversies and future developments are discussed.

Ribonucleases as a novel pro-apoptotic anticancer strategy: review of the preclinical and clinical data for ranpirnase

Cytotoxic ribonucleases (RNases), such as ranpiranase, represent a novel mechanism-based approach to anticancer therapy. These relatively small proteins selectively attack malignant cells, triggering apoptotic response and inhibiting protein synthesis. Ranpirnase, originally isolated from oocytes of Rana pipiens, is a member of a family of endoribonucleases. The anticancer effects of ranpiranase have been documented in both in vitro and in vivo experimental tumor models. The effects of ranpiranase appear to be selective for cancer cells. Based on Phase I study data, the maximum tolerated dose (MTD) was 960 microg/m2, with the dose-limiting toxicity (DLT) characterized by proteinuria with or without azotemia, peripheral edema, and fatigue. Ranpirnase did not induce myelosuppression, mucositis, alopecia, cardiotoxicity, coagulopathy, hepatotoxicity, or adverse metabolic effects. Phase II tumor-specific trials investigated the activity of ranpirnase in malignant mesothelioma, breast cancer, non-small cell lung cancer, and renal cell cancer. A Phase III randomized study in malignant mesothelioma patients compares the combination of ranpirnase plus doxorubicin to doxorubicin monotherapy.

Cisplatin and gemcitabine in malignant pleural mesothelioma: a phase II study

Aims of this study were to evaluate the activity and toxicity of gemcitabine and cisplatin combination in malignant pleural mesothelioma (MPM). Patients with histologically proven MPM, < 75 years of age, Eastern Cooperative Oncology Group (ECOG) performance status (PS) < or = 2, and measurable MPM were eligible. Patients received gemcitabine 1250 mg/m intravenously on days 1 and 8 and cisplatin 75 mg/m on day 2, every 21 days, for a maximum of 6 cycles. From May 1999 to May 2001, 35 chemonaive patients (median age, 61 years) were enrolled. A total of 177 cycles were administered (median 5 cycles; range 1 to 6). One patient was not evaluable for response and toxicity. Nine (26%) patients had partial responses, 11 (32%) patients had progressive disease, and 14 (41%) stable disease. Median survival for all patients was 13 months. Median progression-free survival was 8 months. Grade 3 (World Health Organization) nausea and vomiting occurred in 35% of patients. Grade 3/4 anemia, grade 3/4 thrombocythemia, and grade 3/4 neutropenia were assessed in 24%, 52%, and 61% of patients, respectively. All other side effects were mild. In conclusion, gemcitabine-cisplatin combination seems to be moderately active in MPM. Furthermore, at this dose and schedule, the toxicity profile could be acceptable.

A phase II study evaluating the cisplatin and epirubicin combination in patients with unresectable malignant pleural mesothelioma

Few chemotherapeutic agents have demonstrated their efficacy in malignant mesothelioma. The cisplatin plus doxorubicin combination has one of the highest response rates. Epirubicin is an anthracyclin, analogous to doxorubicin, with a different toxicologic pattern. As there are no data on the activity of the combination cisplatin plus epirubicin in malignant mesothelioma, the European Lung Cancer Working Party (ELCWP) designed a phase II study with response rate as primary objective. Sixty-nine eligible patients with malignant pleural mesothelioma were centrally registered. The majority of the patients were male (n=59), had a Karnofsky performance status of 80 or more (n=62) and presented with an epithelial histologic subtype (n=43). Median age was 62 years. In nine patients, metastases were documented at the initial work-up, mainly in bone, lung and skin. Three hundred and twenty-four cycles of chemotherapy were administered. The main toxicities were nausea and vomiting, neutropenia and alopecia. Among 63 assessable patients, response rate was 19.0% (95% confidence interval [CI] 9-29%). Median survival was 13.3 months. In multivariate analysis, poor prognostic factors for survival were neutrophil count and CALGB groups 4-6. In conclusion, cisplatin plus epirubicin appears as an effective regimen in malignant mesothelioma, with a favourable toxicity profile. However, it does not demonstrate superior activity to other active regimens in this disease.

Triplet Chemotherapy with Cisplatin, Gemcitabine and Vinorelbine for Malignant Pleural Mesothelioma

BACKGROUND

The incidence of malignant pleural mesothelioma (MPM) is expected to increase due to delayed control of occupational exposure to asbestos in Japan. We investigated the use of triplet combination chemotherapy with cisplatin (CDDP), gemcitabine (GEM) and vinorelbine (VNR) for the treatment of Japanese patients with MPM.

METHODS

From December 2000 to August 2003, 12 patients received the following regimen: CDDP 40 mg/m(2), GEM 800 mg/m(2) and VNR 20 mg/m(2) on days 1 and 8 every 4 weeks. Among the 12 patients, six selected patients underwent an extrapleural pneumonectomy (EP) after a median of three cycles of triplet chemotherapy.

RESULTS

The overall response rate for all patients and the response rate for chemotherapy-naive cases were 58 and 67%, respectively. The median survival time and survival rate at 2 years for all patients were 11 months and 50%, respectively. The 2-year survival rates for the patients with and without EP were 83.3 and 16.7%, respectively.

CONCLUSIONS

Triplet chemotherapy with CDDP, GEM and VNR was thus found to be highly effective for patients with MPM and its toxicity was manageable. A multi-institutional phase II trial is now being planned to establish the effectiveness of this new regimen in chemotherapy-naive patients with MPM.

Second-line (post-study) chemotherapy received by patients treated in the phase III trial of pemetrexed plus cisplatin versus cisplatin alone in malignant pleural mesothelioma

BACKGROUND

A phase III trial in patients with malignant pleural mesothelioma demonstrated a survival advantage for pemetrexed plus cisplatin compared with single-agent cisplatin. Because post-study chemotherapy (PSC) may have influenced the outcome of the trial, we examined its use and association with survival.

PATIENTS AND METHODS

Eighty-four patients from the pemetrexed plus cisplatin arm and 105 patients from the single-agent cisplatin arm received PSC. Kaplan-Meier survival estimates were compared by treatment groups, and by PSC and non-PSC subgroups.

RESULTS

The percentage of patients receiving PSC was imbalanced between the treatment arms. Fewer pemetrexed plus cisplatin treated patients received PSC (37.2% versus 47.3%). A multiple regression analysis performed in this trial showed that PSC had a statistically significant correlation with prolonged survival (P <0.01), adjusting for baseline prognostic factors and treatment intervention. The adjusted hazard ratio for PSC over non-PSC subgroups was 0.56 (confidence interval 0.44-0.72).

CONCLUSIONS

PSC in malignant pleural mesothelioma was significantly associated with prolonged survival. It is not known whether the reduced risk of death was associated with PSC or whether patients who had prolonged survival tended to receive more PSC. The pemetrexed plus cisplatin treatment group had a statistically significant survival advantage even though fewer patients from that arm of the trial received PSC. The potentially beneficial role of PSC should be assessed in prospective trials.

Irinotecan for malignant mesothelioma A phase II trial by the Cancer and Leukemia Group B

PURPOSE

The Cancer and Leukemia Group B (CALGB) conducted a multi-center phase II trial to evaluate the activity of irinotecan in malignant mesothelioma (CALGB protocol 9733).

PATIENTS AND METHODS

Twenty-eight patients accrued between January 1998 and January 1999 received irinotecan 125 mg/m2 by intravenous infusion over 90 min weekly for 4 weeks, every 6 weeks. Eligibility included a performance status of 0-2 by CALGB criteria, and no prior chemotherapy. Twenty-five patients had pleural mesothelioma; two patients had peritoneal mesothelioma, and one patient had pericardial mesothelioma. Sixty-one percent of patients had epithelial histology.

RESULTS

There were no complete or partial responders. Thirty-three percent of patients had stable disease and 52% were shown to have progressive disease at the first reassessment. One patient was not evaluable for response. Median survival from study entry was 9.3 months (95% CI 4.5-13.2 months); 1-year survival was estimated at 46% (95% CI 28-65%). Toxicity was moderately severe. Grade 3 or 4 toxicities included neutropenia in 28% of patients, lymphopenia in 43%, and diarrhea in 18%. Three patients died of treatment-related toxicities. All three experienced grade 4 diarrhea, two also had neutropenic sepsis.

CONCLUSION

Single-agent irinotecan in this dose and schedule has considerable toxicity in patients with malignant mesothelioma and has no anti-tumor activity. The relatively long median survival seen in this study principally reflects the prognostic features of the accrued patients.

Pemetrexed in Malignant Pleural Mesothelioma

Purpose: This report describes the data and analysis leading to the approval of pemetrexed (LY 231514, MTA, Alimta, Eli Lilly and Co., Indianapolis, IN) by the U.S. Food and Drug Administration (FDA) of a New Drug Application for the treatment of malignant pleural mesothelioma (MPM).

Experimental Design: The FDA review of the efficacy and safety of pemetrexed assessed in a randomized clinical trial of 448 patients with unresectable MPM comparing pemetrexed plus cisplatin with cisplatin alone, as well as preclinical pharmacology and chemistry data, are described. The basis for marketing approval is discussed.

Results: In one randomized, single-blind, multicenter international trial, 226 patients were randomized to the pemetrexed and cisplatin arm and 222 patients were randomized to cisplatin alone. Median survival times were 12.1 months for pemetrexed and cisplatin and 9.3 months for cisplatin (P = 0.021; hazard ratio, 0.766; 95% confidence interval, 0.61-0.96). Myelosuppression, predominantly neutropenia, was the most common toxicity of pemetrexed plus cisplatin. Other common adverse events were fatigue, leucopenia, nausea, dyspnea, vomiting, chest pain, anemia, thrombocytopenia, and anorexia.

Conclusions: Pemetrexed in combination with cisplatin was approved by the FDA on February 4, 2004 for the treatment of patients with MPM whose disease is either unresectable or who are otherwise not candidates for curative surgery. The recommended dose of pemetrexed is 500 mg/m2 intra venous infusion over 10 minutes on day 1 of each 21-day cycle in combination with 75 mg/m2 cisplatin infused over 2 hours beginning 30 minutes after the pemetrexed infusion. Patients must receive oral folic acid and vitamin B12 injections before the start and during therapy to reduce severe toxicities. Patients should also receive corticosteroids with the chemotherapy to decrease the incidence of skin rash. Approval was based on a demonstration of survival improvement in a single randomized trial. Response rates and time to tumor progression were not included in product labeling because of inconsistencies in assessments among the investigators, independent radiologic reviewers, and the FDA, reflecting the difficulty of radiographic assessments in malignant mesothelioma. Complete prescribing information is available on the FDA Web site at http://www.fda.gov/cder/approval/index.htm.