Pfizer's latest pipeline update reveals that four early-stage clinical projects have been shelved, including a stem cell therapy for a leading cause of blindness.
PF-05206388—originally developed by scientists led by Professor Pete Coffey at University College London (UCL) in the U.K.—consisted of an polymer scaffold carrying stem cell-derived retinal pigment epithelial (RPE) cells that was designed to be implanted into the eye.
The cells were intended to be used to replace those at the back of the eye that are damaged in age-related macular degeneration (AMD), with Pfizer and its collaborators focusing initially on the wet (exudative) form of the disease.
The implant grew out of a research consortium set up by UCL's Institute of Ophthalmology, Moorfields Eye Hospital and the U.K. National Institute for Health Research (NIHR) in 2005, with Pfizer joining in 2009 to try to help develop the concept into a commercial product.
The first patient was treated at Moorfields in 2015, and the intention was to enroll 10 patients into the phase 1 study with a data read-out due in March 2017. A notice on clinicaltrials.gov indicates patient enrolment was suspended in January.
Also on the chopping block at Pfizer are a trio of in-house projects, all of which were in phase 1 testing, as well as cancer med Xtandi (enzalutamide) in breast cancer.
PF-06282999 was under evaluation as a treatment for acute coronary syndrome (ACS) and was a member of the myeloperoxidase (MPO) inhibitor class—a group said to have potential in a range of indications including cardiovascular, inflammatory, and neurodegenerative diseases. MPO is a target that was also in AstraZeneca's sights, but AZ kicked out its candidate, AZD3412 for Parkinson's disease, in April.
Pfizer has also dumped another cardiovascular candidate—monoglyceride lipase (MGLL) inhibitor PF-06818883—which was being developed as a treatment for intracerebral hemorrhage, and glucagon receptor blocker PF-06293620 for type 2 diabetes, the second candidate in this class to be cast aside by the drugmaker in the last few months.
Pfizer also said in its second-quarter 2017 report that it spent $3.49 billion on R&D in the first half of the year, roughly in line with the same period of 2016.