Glaxo's MAGE-A3 Candidate Disappoints Again - Analyst Blog

GlaxoSmithKline's GSK shares fell 1.26% after the company announced disappointing data from the phase III MAGRIT study on its MAGE-A3 cancer immunotherapeutic. The randomized, blinded, placebo-controlled study evaluated the efficacy and safety of the MAGE-A3 cancer immunotherapeutic in patients suffering from stage IB, II and IIIA completely resected non-small cell lung cancer (NSCLC), whose tumors expressed the MAGE-A3 gene.

We note that Glaxo has a collaboration agreement with Agenus Inc. AGEN for the candidate. Agenus shares tumbled 11.63% on the news.

The data from the MAGRIT study revealed that MAGE-A3 cancer immunotherapeutic did not significantly extend disease free survival DFS in both the overall MAGE-A3 positive population and in MAGE-A3-positive patients who did not receive chemotherapy as compared to placebo. With this the candidate failed to meet both its first and second co-primary endpoints.

The Independent Data Monitoring Committee (IDMC) indicated that the safety profile of MAGE-A3 cancer immunotherapeutic is not concerning. Glaxo has decided to continue with the MAGRIT study to assess its third co-primary endpoint. Data from a final analysis is expected in 2015.

We note that MAGE-A3 cancer immunotherapeutic is also being evaluated for stage IIIB/C melanoma with macroscopic nodal disease in patients whose tumors expressed the MAGE-A3 gene and were removed surgically. In Sep 2013, Glaxo had announced that the phase III DERMA study evaluating MAGE-A3 cancer immunotherapeutic in melanoma patients failed to meet its first co-primary endpoint. The IDMC recommended continuation of the DERMA study until its second co-primary endpoint was evaluated. Data related to the second co-primary endpoint is expected in 2015.

Our Take

Given two consecutive setbacks related to the MAGE-A3 cancer immunotherapeutic, our expectations from the candidate are low. We believe even if MAGE-A3 cancer immunotherapeutic is cleared by regulatory authorities, it will be for a much smaller patient population than originally intended.

Glaxo carries a Zacks Rank #4 (Sell). Some better-ranked stocks include Alexion Pharmaceuticals, Inc. ALXN and Alkermes ALKS. Both carry a Zacks Rank #1 (Strong Buy).