Bone Therapeutics halts phase 3 for futility, sinking stock

A bone marrow harvest in progress
The harvesting of bone marrow. (Wikipedia/public domain/Navy news service)

Bone Therapeutics has stopped a phase 3 trial of its autologous cell therapy early for futility. The data committee ruled Preob is unlikely to improve outcomes in patients with osteonecrosis, wiping 25% off Bone Therapeutics’ stock price.

Preob is an autologous osteoblastic cell therapy derived from the bone marrow of patients. Belgium’s Bone Therapeutics thought the cells could help patients with osteonecrosis, a disease arising from loss of blood to the bone. The phase 3 tested this hypothesis by randomizing patients to receive an injection of 20 million Preob cells or placebo on top of the surgical treatment for osteonecrosis. 

Sponsored by GenScript

Accelerate Biologics, Gene and Cell Therapy Product Development partnering with GenScript ProBio

GenScript ProBio is the bio-pharmaceutical CDMO segment of the world’s leading biotech company GenScript, proactively providing end-to-end service from drug discovery to commercialization with professional solutions and efficient processes to accelerate drug development for customers.

Bone Therapeutics’ hypothesis is now in tatters. Looking at data at the halfway point of the two-year trial, an independent committee recommended stopping the study due to overwhelming evidence of the futility of the treatment. Bone Therapeutics has stopped enrollment in the study.

The setback sent shares in Bone Therapeutics spiraling downward and wiped out a near-term sales opportunity. However, the situation could have been worse. Bone Therapeutics had planned to run a phase 2b/3 trial of Preob in the U.S. but scrapped that idea two years ago as part of a partial pivot toward allogeneic cell therapy Allob. By then, Allob had already superseded Preob in osteoporosis.

With Preob floundering in phase 3, off-the-shelf cell therapy Allob is now taking center stage at Bone Therapeutics. Allob successfully completed a phase 1/2a delayed-union fracture trial in September but progress into phase 2b is on hold while Bone Therapeutics industrializes its production process. 

The manufacturing changes have pushed back the start of the phase 2b until the second half of next year. By then, Bone Therapeutics should have published phase 2a data on Allob in spinal fusion. Bone Therapeutics is due to run out of money at the end of the third quarter of 2019. 

Suggested Articles

National COVID-19 test shortages have emphasized testing’s critical role in containing and mitigating the pandemic, but inconvenient truths remain.

Zimmer Biomet has signed a deal to buy A&E Medical, maker of open chest surgery tools, for $250 million in cash.

Roche has received authorization from the FDA for a more accurate COVID-19 blood test capable of measuring the levels of specific antibodies.