Final results from PARAMOUNT trial, a Phase III clinical study of pemetrexed (Alimta?, Eli Lilly and Company) in the continuation maintenance setting, demonstrated improved overall survival in patients with advanced nonsquamous non-small cell lung cancer (NSCLC) treated with pemetrexed continuation maintenance. PARAMOUNT trial results were presented on Monday, June 4, 2012, at the 48th Annual Meeting of the American Society of Clinical Oncology (ASCO) in Chicago, Ill. The overall survival data from PARAMOUNT study were submitted to FDA.
The results represent a paradigm shift in the treatment of lung cancer. Pemetrexed, used as first-line treatment setting, is continued as maintenance therapy in an ongoing effort to control the cancer. Prior to the use of maintenance treatment, physicians typically treated a patient with four to six cycles of chemotherapy and then waited until the disease returned or worsened before treating it again. In PARAMOUNT, pemetrexed was prescribed in combination with cisplatin induction therapy immediately followed by maintenance pemetrexed and best supportive care.
Previous studies
PARAMOUNT builds upon previous studies evaluating the use of pemetrexed as a first-line therapy with cisplatin[1], as well as pemetrexed as a maintenance therapy[2] (following non-pemetrexed-based first-line agents) in patients with advanced nonsquamous NSCLC. However, PARAMOUNT is the first study that evaluated both the use of pemetrexed plus cisplatin therapy followed immediately by the use of pemetrexed in the continuation maintenance setting.
Progression-free survival results
At ASCO 2011, the primary progression-free survival results of PARAMOUNT were presented and showed that pemetrexed continuation maintenance improved progression-free survival, or the time a patient is alive without their disease worsening.[3]
Final results of this multicenter, double-blind, placebo-controlled trial demonstrated a statistically significant 22 percent reduction in the risk of death (HR=0.78). Patients achieved a median overall survival of 13.9 months from randomization (16.9 months from start of induction) on the pemetrexed continuation maintenance arm compared to 11.0 months from randomization (14.0 months from start of induction) on the placebo arm.
“The pemetrexed PARAMOUNT study is the first to show a survival benefit in continuation maintenance ? answering an important question for physicians treating patients with this type of lung cancer,” said Allen S. Melemed, M.D., M.B.A., a senior medical director with Lilly Oncology.
Trial design
A total of 939 patients with advanced nonsquamous NSCLC were enrolled in the study and received pemetrexed (500 mg/m2 on day one of a 21-day cycle) in combination with cisplatin (75 mg/m2) induction therapy. Patients whose disease had not progressed during the pemetrexed + cisplatin induction and had a performance status of 0-1 (n=539) were randomized two-to-one to receive pemetrexed maintenance (500 mg/m2 on day one of a 21-day cycle) plus best supportive care (n=359) or placebo plus best supportive care (n=180) until disease progression. Of randomized patients, 44.9% had either a complete response or partial response and 51.9% had a response of stable disease to pemetrexed plus cisplatin induction treatment. All patients received vitamin B12, folic acid and dexamethasone.
Drug-related adverse events
Overall, the most serious (grade 3/4) drug-related adverse events (AEs) were higher for those treated with pemetrexed continuation maintenance versus placebo (12.5% vs. 0.6% laboratory and 11.4% vs. 4.4% non-laboratory). The most commonly reported grade 3/4 drug-related AEs observed on the pemetrexed arm versus placebo were anemia (6.4% vs. 0.6%), fatigue (4.7% vs. 1.1%), and neutropenia (5.8% vs. 0%). There was one potentially drug-related death on the pemetrexed arm and two on the placebo arm. Discontinuations due to AEs were 18% with pemetrexed and 7% with placebo.
Advanced nonsquamous NSCLC
PARAMOUNT was conducted specifically in patients with advanced nonsquamous NSCLC because past studies have shown that advanced NSCLC patients with a nonsquamous histology (those with the subtypes of adenocarcinoma, large cell carcinoma or “other” histologies) experienced improved efficacy over the relative comparator arm in the trial, when treated with an ALIMTA regimen.[1],[2],[4] Patients with advanced NSCLC with squamous cell histology were not included in the PARAMOUNT study as ALIMTA has not shown to be effective in this patient population relative to the comparators in these previous trials.
Non-Small Cell Lung Cancer (NSCLC)
Globally, lung cancer is the most common form of cancer and the biggest killer, causing 1.3 million cancer deaths annually.[5] About 85 ? 90 percent of all lung cancers are NSCLC.[6] The liver, bones and brain are potential targets if the cancerous cells enter the bloodstream.
NSCLC comprises a group of histologies or tumor types differentiated by cellular structure. Nonsquamous histology includes adenocarcinoma and large cell carcinoma, which account for more than half of all NSCLC diagnoses[7], as well histologies classified as “other.”
References:
[1] Scagliotti GV, Parikh P, von Pawel J, et al. Phase III study comparing cisplatin plus gemcitabine with cisplatin plus pemetrexed in chemotherapy-naive patients with advanced-stage non-small-cell lung cancer. J Clin Oncol 2008; 26: 3543?51.
[2] Ciuleanu T, et al. Maintenance pemetrexed plus best supportive care versus placebo plus best supportive care for non-small-cell lung cancer: a randomised, double-blind, phase 3 study. The Lancet, Vol. 374 No. 9699 pp 1432-1440, October 24, 2009.
[3] Paz-Ares L. G., et al. PARAMOUNT: Phase III study of maintenance pemetrexed (pem) plus best supportive care (BSC) versus placebo plus BSC immediately following induction treatment with pem plus cisplatin for advanced nonsquamous non-small cell lung cancer (NSCLC). J Clin Oncol 29: 2011 (suppl; abstr CRA7510).
[4] Scagliotti GV, Parikh P, von Pawel J, et al. Phase III study comparing cisplatin plus gemcitabine with cisplatin plus pemetrexed in chemotherapy-naive patients with advanced-stage non-small-cell lung cancer. J Clin Oncol 2008; 26: 3543?51.
[5] World Health Organization, Gender in Lung Cancer and Smoking Research, Department of Gender, Women and Health, 2003, http://www.who.int/gender/documents/en/lungcancerlow.pdf, (April 20, 2011).
[6] American Cancer Society, “What Is Non-Small Cell Lung Cancer?,” December 16, 2010, American Cancer Society, Last accessed April 20, 2011).
[7] American Cancer Society, “What Is Non-Small Cell Lung Cancer?,” October 20, 2009, American Cancer Society. Last accessed April 20, 2011.
ASCO Abstract # LBA7507
For more information:
– PubMed Health: Consumer Medication Information – pemetrexed.
– ALIMTA in Maintenance Treatment for Advanced Nonsquamous NSCLC.
