Pfizer is terminating its clinical development programme for investigational PCSK9 inhibitor bococizumab, which was being assessed by the firm for reducing cholesterol.

The drug giant said the decision comes as clinical data and the market landscape indicate that the drug is "not likely to provide value to patients, physicians, or shareholders".

Data from six bococizumab lipid-lowering studies suggest an "unanticipated attenuation of low-density lipoprotein cholesterol (LDL-C) lowering over time", as well as a higher level of immunogenicity and higher rate of injection-site reactions than seen with the other agents in this class, it said.

As a result, two ongoing cardiovascular outcome studies, SPIRE-1 and SPIRE-2, will now be discontinued.

The company has committed to ensuring that the data will be made available to study leaders for independent analysis and prompt public presentation, "to honour the altruism of trial participants, and to maximize the clinical and scientific knowledge derived from the halted trials."

"We believe the available data will allow us to test the core scientific questions posed by the overall program which is in the best interest of patients who volunteered in these clinical trials, and for patients worldwide who suffer from heart disease," said Paul Ridker, co-chair Executive Committee, SPIRE clinical trials program and director for Cardiovascular Disease Prevention, Brigham and Women's Hospital.