Leading the pack is never easy, but today, UNITY Biotechnology is back with some positive news for senolytics.
Being first is not always easy
Unity was the first company focused on clearing senescent cells to appear and led the pack from its founding some years ago. Unfortunately, being the first is not always easy, and UNITY has had setbacks such as the disappointing news in August 2020, which saw its lead candidate UBX0101 essentially fail to work as intended.
UBX0101 is an MDM2-p53 inhibitor designed to treat osteoarthritis of the knee, but, unfortunately, it failed in its trial. There are a number of potential reasons why: it could be that the target tissue just did not contain enough senescent cells using that particular pro-survival pathway for their removal to achieve much, that senescent cell accumulation does not play a key role in osteoarthritis, that the drug simply did not remove senescent cells, or even that senescent cell clearance in humans is not as beneficial as it is in other animals. The reason remains unclear.
Many people were ready to write UNITY off as a failure at this point, but there was always the potential for it to succeed with one of its other drug candidates, as we pointed out earlier this year.
A second shot on goal
Recently, UNITY announced positive results from its phase 1 study of UBX1325 in patients with advanced DME or wet AMD. The study participants had also reached the point where anti–vascular endothelial growth factor therapy (anti-VEGF therapy) had ceased to be useful.
UBX1325 is different from UBX0101 and targets a different pro-survival pathway that senescent cells use to evade apoptosis, a form of programmed self-destruction that cells should initiate when damaged. UBX1325 works by inhibiting Bcl-xL and is the first senolytic drug that has been used in an ophthalmological context.
The study found that UBX1325 is well tolerated, no adverse effects reported, and no dose-limiting toxicities were observed. While phase 1 studies are conducted in order to determine safety, the majority of participants who were administered UBX1325 showed significant improvement in best-corrected visual acuity, central subfield thickness, and subretinal and intraretinal fluid. This is excellent news, as these are all indicative markers of disease progression.
UNITY has announced that it will now be moving to a phase 2a study to further assess the safety and efficacy of UBX1325 in a larger group of participants with DME. The data for this is anticipated for the first part of 2022.
Also, it is going to be enrolling additional patients with advanced wet AMD in the phase 1 study in order to seek data to support a phase 2a study.
Quotes from the press release
“The imaging data demonstrating structural improvements in the retina are compelling at this stage of clinical development and represent defined endpoints for disease improvement,” said Jeffrey Heier, M.D., Director of the Vitreoretinal Service and Retina Research at Ophthalmic Consultants of Boston. “Importantly, UBX1325 is an entirely new treatment modality for eye disease and is particularly exciting for this patient population for whom new therapeutic options could provide significant additional benefits alone or in combination with anti-VEGF agents.” – Source.
Jamie Dananberg, M.D., chief medical officer of UNITY, added, “The patients enrolled in this study had advanced disease for whom anti-VEGF therapies, the standard of care for DME and wet AMD, were no longer thought to be of benefit. Seeing treatment-related improvement in these difficult-to-treat patients is very promising and supports the investigation of UBX1325’s potential as a differentiated, disease-modifying treatment option for a broad patient population. We look forward to further exploring the efficacy of this novel mechanism to alter the course of disease progression in DME patients in the recently initiated Phase 2a study.” – Source.
Tackling the complexity of aging and developing interventions is arguably the greatest challenge humanity has ever faced. Along the way, there will likely be hundreds of failed experiments and studies before the problem is solved. UNITY was the first company to step up and develop senolytic drugs to solve one aspect of aging, and while its first shot on goal missed, this second shot could hit the mark.
The road we have ahead of us is a long one; there will be more failures, and there will be more setbacks, but, importantly, there will also be successes too. We can learn not only through success but also through failure, and as our knowledge and understanding of what aging is and how it works grows, the successes will come more often. This is a good step forward.