Monopar files for $40M IPO to test chemo side effect drug

Monopar Therapeutics has filed to raise $40 million through an IPO. The public financing will enable Monopar to start a phase 3 trial of a prophylactic treatment for a side effect of chemoradiotherapy. 

Illinois-based Monopar licensed the severe oral mucositis treatment, clonidine mucoadhesive buccal tablet Validive, from Onxeo for $1 million upfront in 2017. The deal came two years after the drug failed to drive a statistically significant reduction in incidence of severe oral mucositis in phase 2. 

Onxeo zeroed in on “observed differences in the incidence and time to occurrence” of the side effect to justify its conclusion that further development was warranted. Monopar agreed with the conclusion, leading to a heavily backloaded deal.

Now, Monopar wants investors to put up the cash to enable it to put its belief to the test. The money will equip Monopar to start a phase 3 trial before the end of 2019. Monopar plans to run an adaptive design trial that enables it to perform an interim analysis about 12 months after the study begins. A confirmatory second trial will get underway shortly after the interim analysis.

The design reflects the limitations of the midphase data generated by Onxeo. Monopar thinks the phase 2 missed its primary endpoint because of the “relatively small sample size” but acknowledges the failure “increases the risk of the phase 3 trials.” The adaptive trial is designed to mitigate the risk.

“Our adaptive design approach will allow us to confirm or reject our hypothesis based off the phase 2 data that the optimal patient population for Validive is likely either all [oropharyngeal cancer] (OPC) patients or HPV+ OPC patients, and then run a confirmatory second trial should it be warranted,” Monopar wrote in its IPO filing.

Monopar thinks the IPO funding will see it through to the interim review and potentially into the start of the confirmatory second study. If the interim data are positive, Monopar will have partly derisked the asset and will be in a stronger position to raise money for the rest of the study.