Nabriva’s Antibiotic Contempo Turned Down by FDA Over Manufacturing Issues

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Businessman showing thumbs down.

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Nabriva Therapeutics announced that the Food and Drug Administration (FDA) had issued a Complete Response Letter (CRL) for its New Drug Application (NDA) for Contepo (Fosfomycin) to treat complicated urinary tract infections (cUTI), including acute pyelonephritis.

Nabriva Therapeutics, headquartered in Dublin, Ireland, announced that the Food and Drug Administration (FDA) had issued a Complete Response Letter (CRL) for its New Drug Application (NDA) for Contepo (Fosfomycin) to treat complicated urinary tract infections (cUTI), including acute pyelonephritis.

The rejection was over manufacturing issues, rather than efficacy issues.

The company had a target action date of April 30 for Contepo for serious infections. It was upgraded from an earlier target date of June 30 after a clarification of the classification and subsequent expedited review period for the NDA submitted in October 2018. It was also granted Qualified Infectious Disease Product (QIDP) and Fast Track designations.

Contepo (Fosfomycin for injection) is a novel intravenous antibiotic with a broad spectrum of Gram-negative and Gram-positive activity, including against most multi-drug resistant (MDR) strains such as ESBL-producing Enterobacteriaceae. Intravenous Fosfomycin has been approved for over 45 years in Europe for a variety of infections. Contepo is a new dosing approach originally developed by Zavante, which Nabriva acquired.

The company expects to request a “Type A” meeting with the agency to discuss the CRL. “We will be working with the FDA in the coming weeks to gain a full understanding of the FDA’s comments, with the goal of bringing this important treatment to patients as quickly as possible,” stated Ted Schroeder, Nabriva’s chief executive officer.

About a year ago, Achaogen received an FDA approval for Zemdri (plazomicin), another antibiotic approved for multi-drug resistant (MDR) Gram-negative infections, including cUTI and pyelonephritis. The drug launched in July 2018. At the time, the company announced plans to eliminate 80 jobs, about 28% of its staff, to focus on the launch and two other research programs.

Two weeks ago, the company filed for Chapter 11 bankruptcy reorganization. It hopes to continue normal business operations and took out a $25 million loan from Silicon Valley Bank so it could. Sales of Zemdri have been disappointing, and it wasn’t approved for systemic bloodstream infections, limiting its use.

Another antibiotics company, Melinta Therapeutics, cut staff in November 2018. At the time, the company sent a statement to New Haven Biz, which said, “In the face of an extremely challenging time for the antibiotics industry, Melinta has made the difficult decision to significantly reduce our investment in discovery research and are currently looking for strategic partners to take on these activities, located at our New Haven facility.”

The company’s third-quarter 2018 statements indicate higher costs and lower-than-expected sales for its antibiotics for difficult to treat skin infections and other infectious diseases.

Even if Nabriva eventually gets Contepo approved, it faces a tough market. As a recent Wired article, “The Antibiotics Business Is Broken—But There’s a Fix,” notes, drug development is generally built on the idea that if you spend 10 to 15 years developing a drug and spend at least $1 billion to do so, you can then charge a high enough price or sell enough of the drug to earn back the R&D expenses, reward investors and be profitable.

“That math works for most of the products of the pharmaceutical industry, from old drugs that people take every day—antidepressants, beta-blockers, statins—to the newest cancer therapies known as CAR-T, which can cost almost $500,000 per dose. But antibiotics don’t fit that equation. Unlike cancer drugs, most antibiotics are inexpensive; the few with high price tags are reserved for rare hospital use. And unlike drugs to treat chronic diseases, people take antibiotics for only short periods of time,” Wired wrote.

As a result, big pharma has largely gotten out of the antibiotics business, while about 90% of research on new antibiotics is being conducted by small biotech with market caps of less than $100 million, more than half pre-revenue. And they desperately need funds and revenue to recoup costs and build marketing infrastructure, something that can be difficult to get in the antibiotics business.

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