Amphastar shares tumble after FDA rejection
- Amphastar Pharmaceuticals has received a complete response letter (CRL) from the Food and Drug Administration for its intranasal naloxone for emergency treatment of opioid overdose, the drugmaker announced Tuesday.
- The rejection letter asked for more data on the human factors user study, as well as a device evaluation, and other undisclosed issues, the specialty pharma said.
- Amphastar's shares tumbled by over 20% from close-of-market Friday, trading near $14 per share on Tuesday — well off the company's 52-week high.
Deaths from opioid overdose are climbing, with a four-fold increase since 1999, according to the Centers for Disease Control and Prevention, rising in lockstep with increasing sales of prescription opioids. Deaths have skyrocketed as well, totaling over 33,000 in 2015. In response, a handful of companies are scrambling to meet the need for alternative addiction treatments and for overdose treatments.
Naloxone, a drug which can block or reverse the effect of opioids, has become a key resource to help counteract rising overdose rates. Increasing the availability of naloxone, for example, was one of the FDA's priorities in the action plan it debuted last year.
Amphastar's nasal spray, though, has hit a roadblock with the FDA. The letter from the regulator highlighted "issues including user human factors study, device evaluation, and other items that need to be addressed before the NDA can be approved."
The company didn't give any further details about the CRL, nor did it put forward any timelines on when the CRL might be resolved. In the meantime, the company said it will continue to supply naloxone in pre-filled syringes.
"While we are disappointed to have not received approval at this time, we intend to continue to work with the FDA to address their concerns in the CRL and hope to bring intranasal naloxone to the market as soon as possible," said Amphastar's CEO, Jack Zhang.
Naloxone has been around for some time as an injectable drug. Yet drugmakers have seen an opportunity to improve the delivery vehicle for the drug and make it easier to use.
Adapt Pharma won approval for the first-ever nasal spray of naloxone in late 2015 and Kaleo Pharma has an auto-injector version, Evzio, on the market.
Last summer, Senators Susan Collins and Claire McCaskill sent a letter to Amphastar, Kaleo, Pfizer, Adapt and Mylan asking for more information on the companies' pricing policies and on patient access to the critically important drug.
This isn't Amphastar's first tangle with the FDA, either. In December of last year, Amphastar received a CRL for Primatene Mist, its reformulated OTC inhalable epinephrine formulation. The company aims to address the FDA concerns for that dug by mid-2017.
- Amphastar Pharmaceuticals Statement
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