Eli Lilly and Company received a fourth approval from the US Food and Drug Administration (FDA) for Alimta (pemetrexed for injection). The latest approval is for Alimta as a maintenance therapy for locally advanced or metastatic non-small cell lung cancer (NSCLC), specifically for patients with a nonsquamous histology whose disease has not progressed after four cycles of platinum-based first-line chemotherapy. Alimta is not indicated for treatment of patients with squamous cell non-small cell lung cancer.

NSCLC is the most common form of lung cancer, resulting in more than 180,000 new cases in the US each year. It is defined as a group of histologies, that is, tumour types differentiated by cellular structure. Nonsquamous histology includes adenocarcinoma and large cell carcinoma, which account for more than half of all NSCLC diagnoses, as well as histologies classified as 'other'.

"This FDA approval is encouraging news for non-small cell lung cancer patients, their caregivers and doctors," said Richard Gaynor, vice president of cancer research and global oncology platform leader for Lilly. "It represents an important paradigm shift for NSCLC treatment - maintenance therapy as a way of extending survival in nonsquamous patients, using histology as a way of determining which NSCLC patients may benefit and which may not."

"Previously, patients received best supportive care following their chemotherapy. Now physicians and patients have a new option to improve survival," added Gaynor.

The notion of maintenance therapy in NSCLC is new. Maintenance therapy is treatment given after initial chemotherapy but before new tumour growth. And while pathologists routinely determine the cancer's histology, or tissue type, the use of this information to tailor therapy for potentially better outcomes is also new.

Results from a global, multicenter, double-blind phase-III trial were presented as an oral presentation at the American Society of Clinical Oncology (ASCO) annual meeting in Orlando, Fla. on May 31, 2009 (Abstract # CRA8000) by Chandra Belani, Miriam Beckner distinguished professor of medicine and deputy director of Penn State Cancer Institute at Penn State Milton S Hershey Medical Center.

The trial compared efficacy with respect to overall survival of Alimta 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. The trial supported previous studies looking at the use of histology to tailor treatment for patients with advanced nonsquamous NSCLC.

Patients in the trial were treated with Alimta (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.

In 2004, Alimta received consecutive approvals: it was the first agent to be approved in combination with cisplatin as a treatment for patients with malignant pleural mesothelioma, whose disease is unresectable or who are otherwise not candidates for curative surgery, and then as a single agent for the second-line treatment of patients with locally advanced or metastatic NSCLC after prior chemotherapy treatment.

In 2008, Alimta, in combination with cisplatin, was approved as a first-line treatment for locally advanced or metastatic NSCLC for patients with nonsquamous histology. At the time of the first-line approval, the FDA also approved a change to the second-line indication. Alimta is now indicated as a single agent for the treatment of patients with locally advanced or metastatic, nonsquamous NSCLC after prior chemotherapy. Alimta is not indicated for treatment of patients with squamous cell non-small cell lung cancer.