UNITY Biotechnologies has recently announced an expansion of its first-stage human trial of UBX0101, a drug that has been shown to have senolytic properties in mice  and that the company hopes will be useful in treating painful osteoarthritis of the knee.
An expanded clinical trial
UNITY Biotechnologies, a $495 million biotech company in the process of creating senolytic medicines that target senescent cells, has just announced an expansion of its first-stage human trial of the first drug in its pipeline (UBX0101), which targets painful osteoarthritis of the knee.
This expansion adds 24 patients to the trial, who will be treated with the highest evaluated dose of the drug. This expansion is intended to provide supplemental data for the trial, allowing the company’s researchers to analyze the fluid in the knee joints of patients in order to measure the harmful chemicals (known as the SASP) secreted by senescent cells. Low SASP levels in this fluid suggest that the drug was effective in destroying these harmful cells and may be more likely to be successful in future trials.
Why expand the trial?
While not necessary for the trial itself, this measurement is extremely important, as it will give evidence that the therapy biologically works in humans rather than just in mice. Since the trial’s primary function at this stage is to make sure that the therapy is safe, this additional information will mainly be useful in allowing researchers and investors to know if the drug is likely to be successful in later trial stages or if any further modifications to the therapy or dosage will be necessary (or even possible) to make it viable.
If the drug is found to be ineffective or if the current recommended dosage is too low, this will prevent a doomed second- or third-phase trial from being started, thus saving years of time and millions of investor dollars.
This trial is expected to get results in the second quarter of 2019; in other words, we’ll know if UBX0101 has senolytic effects and if it is toxic between the start of April and the end of June. At that point, the drug will move onto future trials that test how functionally effective it is, if it has any side effects, the correct dosage, and how effective it is compared to current treatments for the same disease.
This trial expansion shows that UNITY wishes to obtain more information about its product’s effectiveness in human patients before proceeding to later phases. While it is too early to say for sure, we remain hopeful that UBX0101 will prove that senolytics can be effective against age-related diseases.
 Jeon, O. H., Kim, C., Laberge, R. M., Demaria, M., Rathod, S., Vasserot, A. P., … & Baker, D. J. (2017). Local clearance of senescent cells attenuates the development of post-traumatic osteoarthritis and creates a pro-regenerative environment. Nature medicine, 23(6), 775.