Pfizer halts development of lung cancer drug

Pfizer has halted a development programme in lung cancer for investigational toll-like receptor agonist, PF-3512676, in combination with cytotoxic chemotherapy.

Pfizer licensed PF- 3512676 from Coley Pharmaceutical in 2005 and the discontinuation included two phase III clinical trials and two phase II clinical trials.

A interim analysis of the phase III clinical trials by an independent Data Safety Monitoring Committee (DSMC) showed there was no evidence that PF-3512676 produced additional clinical efficacy over that achieved with the standard cytotoxic chemotherapy regimen alone. The DSMC concluded that the risk-benefit profile did not justify continuation of the trials. Pfizer agreed with the findings and put a stop to the related clinical trials.

Dr Charles Baum, who is vice-president of Pfizer's R&D, said: "We are communicating these results to patients and the scientific and medical community. While these results show the challenge of bringing new therapies to patients with cancer, Pfizer remains committed to advancing our broad and diverse oncology programs which include over two hundred clinical trials of sixteen new medicines in clinical studies in immunotherapy, signal transduction inhibition and angiogenesis inhibition."

Pfizer shares fell USD 0.34 cents to rest at USD 25.87 in recent trading.

PF-3512676 was not seen as a major potential earner for Pfizer, with Bear Stearns analysts forecasting sales of USD 384m in 2010 had it reached market.

The impact of the discontinuation on co-development partner, Coley Pharmaceutical, a small US-based drug-development company was far more severe. The compound had been Coley's most advanced pipeline candidate, and the company would have earned significant royalty revenue from product sales. Coley shares dropped 56 per cent to USD 3.71 in recent trading.

Coley said in a press statement that the discontinuation of PF-3512676 was surprising, because it showed signs of activity in a smaller, mid-stage trial.