November 29, 2023

After decades, we finally have a new drug to fight super-gonorrhea

After Decades, We Finally Have A New Drug To Fight Super-gonorrhea
This low-resolution photomicrograph reveals the histopathology in an acute case of gonorrhoea. Image via Wikimedia Commons.

In a world grappling with the escalating threat of antibiotic-resistant infections, a groundbreaking development has emerged. Zoliflodacin, a novel antibiotic, marks a significant milestone in the battle against “super-gonorrhoea”, a formidable foe in the realm of sexually transmitted infections (STIs).

Why this matters

Each year, nearly 100 million people worldwide are affected by gonorrhoea, a bacterial infection that can lead to severe health complications if left untreated​​. It gets even worse. Alarmingly, many strains of the bacterium responsible, Neisseria gonorrhoeae, have developed resistance to nearly all available drugs, earning the moniker ‘super-gonorrhoea’. The rise of such drug-resistant strains poses a critical challenge to global health.

In the past few years, this “super-gonorrhoea” has become virtually untreatable in some cases. It’s impervious to almost all drugs. The infection is often asymptomatic and can cause long-term problems such as infertility and ectopic pregnancies.

This is where the new study comes in.

The first new drug in decades for gonorrhoea

In a phase 3 trial conducted in five countries, researchers tested out zoliflodacin.

Zoliflodacin is the first new antibiotic for gonorrhoea in decades, developed by AstraZeneca and later by the company’s spinoff Entasis Therapeutics​​. This novel treatment operates by targeting an essential bacterial enzyme, offering a unique mechanism of action against the pathogen. In the trial conducted across multiple countries, zoliflodacin demonstrated its efficacy, performing as well as the current standard treatment of ceftriaxone and azithromycin​​​​.

“The outcome of this study is a potential game changer for sexual health,” Edward Hook, MD, protocol chair for the trial and Emeritus Professor of Medicine at the University of Alabama-Birmingham, said in a press release from trial co-sponsors Innoviva Specialty Therapeutics and the non-profit Global Antibiotic Research and Development Partnership (GARDP).

The trial’s success signals a potential game-changer because the drug-resistant bacteria haven’t developed immunity to this treatment.

Zoliflodacin not only addresses the immediate need for effective treatment against resistant strains but also offers ease of administration as an oral medication​​​​. This aspect is crucial, especially considering the relative comfort of oral administration compared to intramuscular injections, the current standard.

Drug developed by non-profit

discovering treatments illustration - After Decades, We Finally Have A New Drug To Fight Super-gonorrheadiscovering treatments illustration - After Decades, We Finally Have A New Drug To Fight Super-gonorrhea
Image generated by AI.

Perhaps the most remarkable thing about zoliflodacin is its path to market. The development was significantly funded and managed by a non-profit organization, representing a departure from the traditional pharmaceutical-company-driven model. This approach, focusing on public health needs rather than profit, could revolutionize the way antibiotics are developed, especially for diseases prevalent in lower-income countries​​.

This is especially important because companies are notoriously disincentivized to create new antibiotics.

The development of new antibiotics is costly and time-consuming, often taking over a decade and costing hundreds of millions to billions of dollars. Unlike medicines for chronic conditions, antibiotics are only used for short periods, leading to lower sales and profits. As a result, the world is producing few antibiotics, all while bacteria is building up immunity to existing treatments.

“Gonorrhea is the perfect example of a sexually transmitted infection that will develop resistance to whatever you use on it,” Hook recently told CIDRAP News. “The first antibiotics ever used [for gonorrhea] were sulfa drugs in the 1930s. And now, 90 years later, every antibiotic that’s ever been used to treat gonorrhea, this organism has developed resistance to.”

Entasis Therapeutics Limited signed an agreement with GARDP in 2017 to carry out the phase 3 trial. Per the agreement, GARDP received the rights to commercialize the drug in all low- and middle-income countries. Meanwhile, Innoviva will retain commercial rights in North America, Europe and some parts of Latin America and the Asia-Pacific region.

Zoliflodacin’s journey to the market, spearheaded by this unconventional approach, illustrates the power of public-private partnerships in addressing global health crises. With plans to bring more such treatments to fruition, this model promises to transform the landscape of antibiotic research and development, making essential medicines more available and affordable worldwide.

The success of zoliflodacin is a beacon of hope in a landscape where antibiotic-resistant infections kill more people than HIV or malaria. However, the battle against super-gonorrhoea is far from over. The bacterium has historically developed resistance to all classes of drugs used against it​​. Zoliflodacin’s effectiveness must be preserved through careful and judicious use, with a focus on preventing the development of resistance. At the same time, continuing to develop new drugs is all the more important.