Proteostasis Appoints 7 CF Experts to Guide Design of PTI-428 Phase 3 Program

An advisory committee composed by experts in the field of cystic fibrosis will help to guide the design of the global Phase 3 program testing PTI-428, the company developing the potential treatment, Proteostasis Therapeutics, announced.

Its formation is a key step in ensuring that the program follows regulatory requirements, while retaining the power to demonstrate the potential of the investigative drug, Proteostasis said in its press release.  The guidance of the independent Steering Committee will also be important to increase the possibilities of future approval of PTI-428.

PTI-428 is being developed to increase the amount of the cystic fibrosis transmembrane conductance regulator (CFTR) — the protein that is defective in CF patients. When combined with other CFTR modulators, such as Orkambi (lumacaftor/ivacaftor) and Symdeko (tezacaftor/ivacaftor and ivacaftor), it may improve treatment effectiveness and patient outcomes.

PTI-428 has been granted Fast Track, Orphan Drug, and Breakthrough Therapy designations by the U.S. Food and Drug Administration.

The committee will be led by Jennifer L. Taylor-Cousar, MD, co-director and CF Therapeutics Development Network Director for the Adult CF Program at National Jewish Health. She previously served as co-lead investigator of the pivotal study on Symdeko in CF patients. Currently, she is leading a Phase 2 trial that is testing PTI-428 in patients using Symdeko, a Vertex treatment.

“I look forward to working … to design a Phase 3 program for PTI’s amplifier that could potentially provide evidence of its ability to improve the quality of life for a significant portion of the CF community,” Taylor-Cousar said in the release.

Other committee members include:

• Mark A. De Rosch, PhD, senior vice president of Regulatory Affairs and Quality Assurance at Nightstar Therapeutics, who was previously involved in the process of approval of Kalydeco.
• Scott H. Donaldson, MD, an associate director and professor at the University of North Carolina Clinical and Translational Research Center (CRTC), who was previously lead author for the Phase 2 study assessing Symdeko.
• Patrick Flume, MD, professor at the Medical University of South Carolina and  a principal investigator of Symdeko’s Phase 3 EXTEND trial (NCT02565914).
• Nicole Mayer Hamblett, PhD, professor at the University of Washington, who is also the co-executive director of the CF Foundation’s Therapeutics Development Network (TDN) Coordinating Center.
• Richard B. Moss, MD, former chief of the Pediatric Pulmonary and Allergy Divisions at Stanford University, who is a co-author of the PROGRESS trial (NCT01931839) assessing the long-term efficacy and safety of Orkambi.
• Carsten Schwarz, MD, head of the Adult Cystic Fibrosis Centre Department of Pediatric Pneumology and Immunology at Charité – Universitätsmedizin Berlin, and a member of the European Cystic Fibrosis Conference Committee.

“We are thrilled to have recruited such a distinguished group of clinicians and researchers to our PTI-428 Phase 3 Program Steering Committee,” said Meenu Chhabra, president and CEO of Proteostasis Therapeutics.

“This committee will provide invaluable guidance to PTI’s Phase 3 development strategy pursuing a broad indication for PTI-428 as an add-on to CFTR small molecule modulator based treatment. … we aim to demonstrate the potential of PTI-428 to improve the efficacy of current or future standard of care,” Chhabra added.