Zosano goes bankrupt after FDA rejects migraine drug delivery patch

Zosano Pharma has run out of road. After working to find a strategic alternative in the wake of the FDA’s refusal to review its submission, the transdermal drug delivery specialist has now filed for paperwork for Chapter 11 bankruptcy.

California-based Zosano has worked in recent years to win approval for a patch that uses microneedles to deliver the selective serotonin receptor agonist zolmitriptan through the skin. By delivering the drug transdermally, rather than via the typical oral route, Zosano sought to accelerate absorption and thereby improve the treatment of migraine. 

However, the company received a frosty reception from the FDA. The agency issued a complete response letter in 2020 and then refused to review Zosano’s resubmission earlier this year. Zosano responded by making two rounds of layoffs and suspending the program. 

The cuts bought Zosano time as it sought to find a financial or strategic alternative. Having seen its cash reserves dip below $10 million last month, Zosano is now out of time. The lack of a company-saving deal has led Zosano to the bankruptcy court. 

Zosano’s Chapter 11 filing reveals it has more than 200 creditors. The list of the creditors with the largest unsecured claims is topped by Patheon, the contract manufacturing wing of Thermo Fisher Scientific. Patheon’s claim, which is disputed, is $2.4 million. Material science company Aptar CSP Technologies, real estate business BioMed Realty and CRO Worldwide Clinical Trials occupy the next three spots. 

To cover its claims, Zosano intends to sell “substantially all of its assets during the bankruptcy case.” Until then, the company is seeking court approval to enable it to continue its ordinary course operations and to facilitate an orderly wind down.