It was good news for Bristol-Myers Squibb yesterday after the US Food and Drug Administration decided to undertake a speedy review of its experimental advanced melanoma candidate ipilimumab.

A priority review is given to drugs that potentially offer significant advances in treatment or address an unmet medical need, and based on the agency’s six-month timeframe for assessing such medicines the company should have a decision by Christmas day.

Ipilimumab is a novel T-cell potentiator that works by blocking the inhibitory signal of CTLA-4 (cytotoxic T lymphocyte-associated antigen 4), a molecule on T-cells that plays a vital role in the regulation of normal immune responses, which boosts the immune system’s T-cell response.

The drug’s filing is based on data from a the pivotal MDX010-020 trial, published online in the <i>New England Journal of Medicine</i>, which compared the overall survival rate of patients taking ipilimumab plus a vaccine known as glycoprotein (gp100), just ipilimumab, and gp100 (the control) alone.

Patients receiving ipilimumab, both with or without the gp100 vaccine, survived for around 10 months, compared to just six months for those given the gp100 alone, clearly demonstrating a survival benefit for patients.

Ipilimumab is also currently under review with regulators in Europe and elsewhere for the treatment of adult patients with previously treated advanced melanoma.