Eli Lilly and Company announced that the European Commission has granted approval for the use of Alimta (pemetrexed for injection) as monotherapy for maintenance treatment of patients with other than predominantly squamous cell histology in locally-advanced or metastatic non-small cell lung cancer (NSCLC), whose disease has not progressed immediately following platinum-based chemotherapy. This approval is based on data that showed pemetrexed improved overall survival in other than predominantly squamous NSCLC patients in the maintenance setting.

Pemetrexed is a chemotherapy agent currently approved for first-line treatment of advanced, other than predominantly squamous NSCLC in combination with a platinum-based chemotherapy, and as a single agent in the second-line setting for advanced, other than predominantly squamous NSCLC patients with recurrent disease.

NSCLC is defined as a group of histologies, that is, tumour types differentiated by cellular structure. Other than predominantly squamous histology, also referred to as nonsquamous histology, includes adenocarcinoma and large cell carcinoma, which account for more than half of all NSCLC diagnoses, as well histologies classified as 'other'.

The concept of maintenance therapy represents a paradigm shift in the treatment of advanced, other than predominantly squamous NSCLC. Traditionally, patients who respond to first-line chemotherapy are monitored until the disease recurs and are then treated with a second-line regimen. In maintenance therapy, rather than halting further treatment until disease progression, patients who respond to a first-line therapy are treated immediately with a maintenance regimen.

"The idea behind Alimta as maintenance therapy for nonsquamous, non-small cell lung cancer is to treat patients immediately following their initial course of therapy, in an effort to prolong survival," said Richard Gaynor, vice president, cancer research and global oncology platform leader at Lilly. "The study that led to this approval was the first that showed improved overall survival in the maintenance setting for NSCLC. This was also the third trial to show the benefit of tailoring Alimta treatment to the nonsquamous NSCLC patient population."

Overall survival data for pemetrexed as a maintenance therapy for NSCLC was presented on May 31, 2009, at the 45th Annual Meeting of the American Society of Clinical Oncology (ASCO).

The trial compared efficacy with respect to overall survival of pemetrexed plus best supportive care versus placebo plus best supportive care in 663 patients with stage IIIB/IV NSCLC whose disease had not progressed after four cycles of platinum-based induction chemotherapy. Pemetrexed was not included among the induction regimens studied in the maintenance trial. The trial supported two previous studies looking at the use of histology to tailor treatment for patients with advanced, other than predominantly squamous NSCLC.

Patients in the trial were treated with pemetrexed (500 mg/m2 on day one of each 21-day cycle) plus best supportive care or placebo plus best supportive care. All patients were supplemented with vitamin B12, folic acid and dexamethasone.

This latest approval for pemetrexed - the fourth in Europe - follows an initial positive opinion issued by the European Medicines Agency's (EMEA) Committee for Medicinal Products for Human Use (CHMP) on May 29, 2009, and the recent approval by the US Food and Drug Administration (FDA) of pemetrexed for maintenance therapy in advanced, nonsquamous NSCLC patients whose disease has not progressed after four cycles of platinum-based first-line chemotherapy.

Apart from the existing approvals in the EU and US for the use of pemetrexed in the treatment of patients with locally-advanced or metastatic other than predominantly squamous NSCLC, pemetrexed is also approved, in combination with cisplatin, in both the EU and U.S. for the treatment of chemotherapy naive patients with unresectable malignant pleural mesothelioma.