Pfizer has halted the global clinical development program for bococizumab, its investigational proprotein convertase subtilisin kexin type 9 inhibitor (PCSK9i) that was being developed as a lipid-lowering agent to treat high cholesterol. In a statement, Pfizer said that total clinical data to date indicate that bococizumab is not likely to provide value to patients, physicians, or shareholders and, as a result, Pfizer has decided to discontinue the development program, including two ongoing cardiovascular outcome studies.

Pfizer said it is ensuring that all regulatory authorities are informed and that all trial investigators are informed and instructed on the next steps. It is estimated that the discontinuation of the bococizumab development program will have a negative impact of approximately $0.04 per share on both a GAAP and adjusted basis. Pfizer will record this as a research and development charge in the fourth quarter of 2016.

PCSK inhibitors are a new class of anti-cholesterol drugs that are said to have blockbuster potential. Two such PCSK inhibitors that are on the market are Amgen’s and Astellas Pharma’s Repatha (evolocumab) and Sanofi’s and Regeneron Pharmaceuticals’ Praluent (alirocumab). A recent Thomson Reuters analysis has ranked Praluent and Repatha to be among the top-10 selling potential blockbuster drugs in 2019, with projected sales of $1.957 billion and $1.994 billion, respectively. Pfizer’s bocoizumab would have faced these competitors should it have had gone to market.

Sanofi/Regeneron’s Praluent is a monoclonal antibody targeting PCSK9 and is competing against Amgen/Astella Pharma’s Repatha. Praluent became the first PCSK9 inhibitor to be approved in the US in July 2015, followed by an approval in the Eurpean Union (EU) in September 2015. In the US, the indication for Praluent was limited to a subset of patients predisposed to high cholesterolemia at the limit of their statin therapy.

Amgen/Astellas Pharma’s Repatha is also a human monoclonal antibody that inhibits PCSK9. It was approved in the EU in July 2015, followed by approval by the US FDA in August 2015. The FDA also limited the Repatha indication to a subset of patients predisposed to high cholesterolemia at the limit of their statin therapy.

Source: Pfizer