The US Food and Drug Administration (FDA) has published a new draft guidance on the development of antibacterial drugs intended to treat "uncomplicated" gonorrhea, the latest in a string of guidance documents reflecting the agency's new thinking on antibiotic development.

Background

In the last few years, FDA has released a bevy of guidance documents aimed at making it easier for companies to develop antibiotic products by easing requirements around clinical trials.

In July 2013, for example, it released its Antibacterial Therapies for Patients with Unmet Medical Need for the Treatment of Serious Bacterial Diseases, which is a sort of overarching guidance meant for products intended to treat serious bacterial diseases in patients with unmet medical needs, or narrow-spectrum antibiotics focused on a single type of pathogen.

It has also recently released guidance documents on developing antibiotics for community-acquired pneumonia,  bacterial pneumonia, abdominal infections and bacterial skin infections.

At the heart of many of these documents seems to be a desire on the part of FDA to make it easier to develop antibiotics—a development welcomed by industry, which has found it increasingly difficult to get antimicrobial products approved in recent years, and the return on their investments becoming ever smaller.

FDA's abdominal infection products guidance, for example, says FDA will consider even a single well-controlled Phase III clinical trial suitable for approving a product under certain circumstances. For many products, it asks for two or more Phase III trials.

In many of the guidance documents, FDA also says it will allow patients who have been previously treated with antibiotics to enroll, dismantling a hurdle that had made it especially difficult to find patients to enroll in trials.

FDA also focuses extensively on endpoints in its guidance documents, and explains in some of them that showing noninferiority may be acceptable to obtain approval, though not in all cases.

New Gonorrhea Guidance

FDA is now out with a new antibiotics guidance, Uncomplicated Gonorrhea: Developing Drugs for Treatment, which is philosophically similar to its recent guidance documents.

In it, FDA notes that sexually transmitted diseases (STDs) like gonorrhea are quite prevalent, with more than 800,000 cases per year in the US alone. More alarming, however, is the rate at which gonorrhea is becoming resistant to existing antibiotics, highlighting what FDA calls "the need for the development of new antibacterial drugs for the treatment of gonorrhea."

The good news for companies: FDA is again willing to accept a single, well-controlled non-inferiority trial as evidence of effectiveness, though in some cases it says it will want two unless the first trial showcased a "compelling outcome."

Similar to its guidance on bacterial pneumonia, FDA said it will also ask that sponsors maintain a safety database involving, at a minimum, 500 patients.

And like other guidance documents, FDA also says that treatment with an antibiotic prior to enrollment is not necessarily a precluding factor. Rather, if the patient has been treated prior to enrollment unsuccessfully, then they are eligible to enroll. Patients who were treated by an "effective antibacterial therapy" will not be eligible to enroll, though the agency offers scant evidence of what it defines as "effective."

Active comparators should be used in the study (e.g. no placebos), and sponsors should use the primary endpoints of a negative culture (i.e. the infection is cured) at the infection site approximately three to seven days after administration of the drug.

A 90-day comment period is now open on the draft guidance, FDA said in a Federal Register posting.

Uncomplicated Gonorrhea: Developing Drugs for Treatment (FR)