Only seven new drugs are in development for the treatment of infections caused by an especially nasty class of superbugs that include E. coli and CRE, the so-called "nightmare bacteria" that the U.S. Centers for Disease Control and Prevention raised alarms about last month.
The data come from the latest report by the Infectious Diseases Society of America, or IDSA, released on Thursday, which has been tracking the rising number of bacteria that resist even the most potent antibiotics.
"We're on the precipice of returning to the dark days before antibiotics enabled safer surgery, chemotherapy and the care of premature infants," said Dr. Helen Boucher, an infectious diseases expert at Tufts Medical Center in Boston and a member of IDSA's board, whose report was published online in Clinical Infectious Diseases.
"Simply put, the antibiotic pipeline is on life support and novel solutions are required to resuscitate it - now," IDSA President Dr. David Relman said in a statement.
Boucher said health officials are losing ground because companies are not developing drugs quickly enough to keep up with the superbugs' ability to develop resistance, adding: "We're all at risk."
Almost as soon as penicillin was introduced in the 1940s, bacteria began to develop resistance to its effects, prompting researchers to develop many new generations of antibiotics. But their overuse and misuse have helped fuel the rise of drug-resistant superbugs.
In the past month, public health officials in the United States and Britain have sounded alarms about the growing threat.
On March 5 the CDC warned of the spread of Carbapenem-Resistant Enterobacteriaceae (CRE), a class of what CDC Director Thomas Frieden called "nightmare bacteria" that kill up to half of patients who get bloodstream infections from them.
A week later, Sally Davies, the chief medical officer for England, said antibiotic resistance was a "catastrophic threat" and called for global action to fill a drug "discovery void."
The latest report, a follow-up to a 2009 study, is based on interviews with drug companies, published data, information culled from websites and other sources. It focuses on new agents to fight gram-negative superbugs, which the group said represent the most "pressing clinical needs."
Gram-negative bacteria include E. coli, Salmonella, Shigella and other species in the class known as Enterobacteriaceae bacteria.
It suggests that companies have continued their retreat from research and development of antibiotics.
"The number of antibacterial compounds in phase 2 or 3 development remains alarmingly low," Boucher and colleagues wrote.
Unlike drugs for chronic diseases such as diabetes, which are taken over many years, antibiotics are used for just a few weeks, and efforts to control resistance have led doctors to prescribe the drugs sparingly.
For the report, Boucher and colleagues focused on new oral or intravenous antibiotics that had progressed to phase 2 or phase 3 clinical trials.
They found a total of seven drugs in development and being tested in people with drug-resistant, gram-negative infections.
"We know not all of those drugs will make it," Boucher said in a telephone interview.
Of the seven, one company, Polymedix, filed for Chapter 7 bankruptcy this month, and AstraZeneca, which is making two of the drugs, last month said it would invest less money in developing antibiotics.
The other companies include Merck, Cubist Pharmaceuticals, GlaxoSmithKline and privately held Achaogen Inc of South San Francisco, California.
The ISDA is pushing for new economic incentives for drug companies, a clarification of U.S. regulations for antibiotic approval, more funding for basic research, better infection-prevention efforts and better data on the spread of drug resistance and the use of antibiotics.