Regulators recently approved ProMetic’s Investigational New Drug application for PBI-4050 and the company’s design for pivotal Phase 2/3 clinical trials of the therapy. A pivotal trial is one that can provide the FDA with the evidence it needs to approve a drug.
PBI-4050 is designed to regulate lung inflammation and tissue scarring. It reduces levels of cytokines, or chemical signals that promote scarring. It also inhibits two other processes involved in scarring, or fibrosis: fibrocyte differentiation and microfibroblast activation. Fibrocytes differentiate — or evolve into — fibrosis-promoting cells known as fibroblasts. Microfibroblast activation gets the fibrosis process started.
A number of studies have demonstrated that PBI-4050 can inhibit fibrosis in key organs, including the lungs, kidneys, heart and liver.
“The treatment options for patients with fibrotic diseases like IPF are limited in scope and effectiveness,” Pierre Laurin, ProMetic’s president and chief executive officer, said in a press release.
“Fast Track designation will allow us to advance PBI-4050 and seek to potentially gain approval in a more efficient process,” he said. “PBI-4050 has the potential to provide patients with IPF a more effective treatment option. We look forward to demonstrating PBI-4050’s clinical efficacy and strong safety and tolerability profiles in a longer-term, placebo-controlled trial.”
A Fast Track designation is aimed at accelerating the development and regulatory review of drugs meeting urgent needs. To receive the designation, a therapy candidate must demonstrate an advantage over currently available treatments. It can be more effective or be able to meet an unmet medical need, for example. Or it can be less toxic or have fewer side effects.
ProMetic presented the results of a Phase 2 (NCT02538536) trial of PBI-4050 in IPF patients at the 2017 American Thoracic Society International Conference in San Diego in May 2017. The study, completed in January 2017, showed that PBI-4050 was safe and that patients tolerated it well. Participants received the therapy alone or in combination with either Boehringer Ingelheim’s Ofev (nintedanib) or Genentech’s Esbriet (pirfenidone), two drugs the FDA has approved for treating IPF.
The Esbriet combination offered little benefit, researchers said. But the Ofev combo led to less lung function decline than in the placebo-treated group. Researchers used forced vital capacity to measure lung function. That is the amount of air a person can exhale after a deep breath.