Untreatable Gonorrhea Threat Has Drugmakers Sprinting for New Cures

A rise in gonorrhea infections has drugmakers racing to develop new therapies as the sexually transmitted infection increasingly evades the last medication that can effectively treat it.

(Bloomberg) — A rise in gonorrhea infections has drugmakers racing to develop new therapies as the sexually transmitted infection increasingly evades the last medication that can effectively treat it.

Resistant strains are surfacing around the world, and experts say they’ll soon arrive in the US. Two companies, GSK Plc and Innoviva Inc., have new antibiotics for gonorrhea in late-stage trials, with results expected in months.

Strains of the bacteria that cause gonorrhea have become impervious to nearly every treatment. In the US, an injection called ceftriaxone is the last antibiotic the Centers for Disease Control and Prevention still recommends for the disease. Even that drug has failed to treat patients in France, Japan, the UK and several other countries.

The race against drug-resistant gonorrhea shows a broader challenge the world faces: Antibiotics developed since the discovery of penicillin are losing their potency as pathogens evolve better defenses, and the pipeline of new therapies isn’t keeping up.

If untreatable strains of gonorrhea become widespread before new medicines reach the market, “we’d be back to the pre-antibiotic era” of the early 20th century, said Jeffrey Klausner, professor of medicine and public health at the University of Southern California. 

Cases Double

More than 80 million people globally caught gonorrhea in 2020, the World Health Organization estimates, with about 1.6 million cases in the US. The infection can cause painful urination and inflammation, and it can lead to complications including infertility if untreated. It’s primarily transmitted through sexual contact, though newborns can also be infected during delivery.

After years of falling cases, sexually transmitted infections have made a comeback in the US. The rate of reported gonorrhea infections more than doubled from 2009 to 2021. Syphilis and chlamydia infections have spiked as well, with doctors rationing a syphilis treatment in shortage.

Gonorrhea is more likely to develop resistance than those diseases, and a rise in overall infections gives it more chances to adapt. For now, ceftriaxone remains a viable treatment in the US. In 2021 only one case in every 1,000 showed decreased susceptibility to the drug.

The drug could lose its potency in the US in the next five years, said Klausner, a former director of sexually transmitted disease prevention and control for the San Francisco Department of Public Health. Doctors may be able to use a combination of other drugs in cases when ceftriaxone fails, according to the CDC.

A new strain found this year in Massachusetts that showed elevated defenses against a wide range of antibiotics raised alarms. “It’s only a matter of time” before strains with deeper resistance arise, said Katherine Hsu, medical director of the Division of STD Prevention and HIV/AIDS Surveillance in the state’s public health department.

Trials Underway

The months ahead will show whether the drug industry can outpace gonnorhea’s adaptation. In early trials, two drugs in development treated gonorrhea more than 95% of the time in genital infections, though one was less effective in infections in the throat that are harder to treat.

Innoviva, a small Burlingame, California, drug company, has a new antibiotic candidate for gonorrhea called zoliflodacin. A nonprofit collaborative called the Global Antibiotic Research & Development Partnership is running final-stage trials for the drug in exchange for the rights to distribute it in low-income countries. Innoviva retains the rights in major markets in North America, Europe and the Asia-Pacific region.

Data from the trial is expected in the last three months of this year. The company sees a “significant unmet medical need with a meaningful opportunity,” Innoviva Chief Medical Officer Margaret Koziel said in an email.

UK drug giant GSK expects data in the first half of next year from late-stage trials of a therapy called gepotidacin in gonorrhea, spokesperson Kate Kanaby said. The company has completed trials of the treatment for urinary tract infections and is preparing to ask regulators in the US and the European Union for approval for that indication.

“GSK sees significant opportunity to lead” the fight against drug-resistant infections, Kanaby said in an email. With competition in the market decreasing, the company expects peak revenue of £2 billion ($2.6 billion) a year from gepotidacin and two other anti-infectives.

GSK also has a candidate for a gonorrhea vaccine in a mid-stage trial, and US regulators have flagged it for accelerated review. The company expects to start late-stage tests in 2026.

Better Tests

Sexual health programs have seen budget cuts in recent years, leading to less screening. The recent debt-ceiling deal eliminated $400 million in grants for specialists who combat sexually transmitted infections.

The CDC is studying the effect of the cuts, the agency said in a statement. Both the agency and the White House strategies to fight STIs call for continued monitoring for resistant cases and developing better tests.

That could help old drugs work again, said Kelly Wroblewski, director of infectious disease at the Association of Public Health Laboratories. Some gonorrhea cases still respond to older treatments, but it’s hard to know which ones.

More precise molecular tests could help doctors find the medications that still work against a particular infection and pick the right one for that patient. While Roche Holding AG sells a molecular test for resistance in Europe, none are approved by the Food and Drug Administration in the US yet.

More attention — and funding — is needed to screen people for gonorrhea and connect them with treatment, said Elizabeth Finley, director of communications for the National Coalition of STD Directors.

“We don’t think it’s a high enough priority,” she said. “No new antibiotic or vaccine will reach someone who can’t make their way to an STI clinic or who isn’t aware that they should go.”

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