As part of a strategic restructuring, Proteostasis is laying off 13 members of its R&D workforce.
As part of a strategic restructuring, Proteostasis Therapeutics is laying off 13 members of its research-and-development workforce.
The company focuses on protein homeostasis, with a particular effort on characterizing and developing therapeutics to control the Proteostasis Network (PN), which are pathways that control protein biosynthesis, folding, trafficking, and clearance. It has implications for a number of diseases, including cystic fibrosis (CF), Alzheimer’s disease, Huntington’s disease, and Parkinson’s disease.
The company’s restructuring is to prioritize its resources on its CF programs, including clinical trials for PTI-428, PTI-801 and PTI-808, in addition to its discovery-stage program in unfolded protein response (UPR) which it is collaborating on with Astellas Pharma.
It expects to save $3 million with its job cuts, with a one-time cash charge in the fourth quarter of this year of about $0.2 million.
“Through our disease relevant technology, or DRT, platform which was established on our understanding of the proteostasis network, we have explored developing drug candidates for a variety of protein conformational diseases,” said Meenu Chhabra, president and chief executive officer of Proteostasis, in a statement. “We have validated our DRT platform through identification of three novel CFTR modulators now in clinical development for CF and an active corporate partnership with Astellas. Our company was founded on the scientific premise that small molecules can restore the balance in the proteostasis network and have therapeutic applications in multiple genetic, degenerative and metabolic diseases. As we move forward, our focus will be in continuing the clinical development of the CF pipeline and advancing the understanding of the underlying biology of our novel CFTR modulators.”
In late July, the company provided updates on its CF programs. It had completed dosing of 19 patients as part of its Phase I/II clinical trial of PTI-428, the company’s CFTR amplifier. The drug was administered with background Orkambi (lumacaftor/ivacaftor) or as the only CFTR modulator in CF patients over a 14-day period. The trial met its primary safety and pharmacokinetic endpoints.
In the Phase I part of its PTI-428 study, 11 subjects in the Orkambi cohort and eight in the PTI-428 monotherapy cohort were enrolled, with each group having two patients on placebo. Side effects were mild or moderate. The company stated, “In the subjects who received PTI-428 in addition to their background Orkambi, there was no significant improvement of FEV compared to placebo, although there was a numerical increase in FEV at day 7. Measurements of sweat chloride and mRNA in nasal mucosa were used as exploratory biomarkers but the changes were not significant nor correlated with lung function changes.”
At the same time, the company announced the protocol for the CF part of its Phase I/II trial of PTI-801, a new generation CFTR corrector that was given Fast Track designation by the U.S. Food and Drug Administration (FDA) and been endorsed by the Cystic Fibrosis Foundation Therapeutics Development Network (TDN) Protocol Review Committee and the European Cystic Fibrosis Society Clinical Trial Network (CTN). Screen for those patients was initiated in August.
It had also started a Phase I trial of PTI-808, a CFTR potentiator in healthy volunteers.
