Xbrane Biopharma announced that it will conduct a clinical trial in prostate cancer patients to assess Spherotide, its one-month generic formulation of Trelstar (triptorelin), to support its plans to submit a Marketing Authorization Application (MAA) to the European Union for approval.
The single clinical study was advised by the German Federal Institute for Drugs and Medical Devices (BfArM), which reviewed the clinical and regulatory aspects of the company’s MAA for the generic.
The active substance in Spherotide is triptorelin, a molecule similar to the gonadotropin-releasing hormone (GnHR), that is used to treat hormone-responsive cancers, such as prostate cancer. Spherotide encapsulates triptorelin in biodegradable microspheres that degrade in the body after the its subcutaneous or intra-muscular injection. The microspheres allow for a controlled release and a long-acting effect, the company said in its press release.
In the clinical trial, expected to enroll 150–170 prostate cancer patients and start in the first half of 2017, the efficacy of Spherotide will be evaluated primarily according to the levels of testosterone suppression seen in patients — with a goal of lowering them to under surgical castration levels — by day 28. A number of secondary endpoints will also be assessed.
Preclinical studies in male rats showed that Spherotide has a similar effect in reducing testosterone levels as Trelstar.
“We are happy to gain support for our regulatory and clinical strategy in discussions with BfArM,” said Martin Åmark, CEO of Xbrane Biopharma. “The advice was pragmatic and concrete and we are very confident that the discussed thresholds for efficacy are achievable. This allows us to proceed with all activities required for finalizing the MAA for the European Union.”
Trelstar is marketed in Europe as Decapeptyl, and according to Xbrane, Spherotide is the only generic triptorelin formulation being readied for market approval as a prostate cancer treatment.
If granted, the MAA will allow Xbrane to make Spherotide commercially available across much of Europe, and will facilitate a similar process in other regions. The generic is not approved by the U.S. Food and Drug Administration.
Xbrane is also developing a three-month formulation of Spherotide.