Paradigm Biopharmaceuticals (ASX:PAR) agreed to return the $2 million of funds it recently received from Obsidian Global under a fourth-tranche drawdown of its convertible note facility, according to a Thursday filing with the Australian bourse.

The 2 million convertible notes issued in connection with the drawdown will be cancelled, and no premium, redemption amount, or other amount is payable by Paradigm under the arrangement, per the filing.

The development follows the interim efficacy result for Paradigm's phase 3 trial of injectable pentosan polysulfate sodium for the treatment of knee osteoarthritis failing to reach the threshold required for the study to proceed.

The company is reviewing data to better understand what impact that trial result will have on its financial position and future operations.