Scientists believe they have found a tuberculosis (TB) drug that could succeed where others are failing.
Resistance and compliance are big treatment problems
Although it is still at a very early stage of testing, the antibiotic appears to work much faster than other TB drugs and treats resistant strains.
Small trials suggest it is safe in humans and further tests are underway, the Belgian team told Science.
No new TB drug has been introduced for over 30 years and is desperately needed, say experts.
It is one of a number of hopeful candidates that are being tested as potential TB therapies.
But experts warned patients it could be 10 years before any of these become available.
One problem with current drug cocktails used to treat TB is that they are long, requiring the person to take as many as six tablets for six to eight months.
This can mean patients don't take the full course.
In turn, this contributes to the second problem - the development of resistant strains of the bacterium that no longer respond to the drugs.
There are about 10m new cases of TB each year, and about 2m TB deaths worldwide, according to the World Health Organization (WHO), and drug resistance is increasing.
The antibiotic discovered by the Johnson & Johnson Pharmaceutical team belongs to a family of drugs called the diarylquinolines or DARQs.
It works in a completely different way to all other known antibiotics by shutting off the energy source used by bacteria.
Experiments in mice show the drug is effective against several different strains of the bacteria that cause TB, including strains that are resistant to other TB drugs.
A month of the treatment cleared the same amount of infection as two months of the standard cocktail of TB treatment in mice.
The ultimate hope is that the drug will do the same in humans when it is given along with two of the standard TB drugs used today.
An added bonus is that, if proven to be safe and effective, the antibiotic could replace one of the drugs in the current TB cocktail that interferes with HIV treatments when taken at the same time.
Lead researcher Dr Koen Andries said: "We really do think we have a very interesting compound."
Chris Dye from the WHO said: "Given the high rates of drug resistant TB that we are seeing, especially in former Soviet countries, it is hugely worrying that no new anti-TB drug has been discovered for over 30 years.
"We eagerly await the results of clinical trials in humans.
"If the efficacy is as good in human TB patients and if the course of treatment could be made shorter by using this drug, say two months instead of six, this would be a big step forward for TB control."
Professor Peter Davies of TB Alert said: "It's good news. We need to reduce the length that people have to take drugs for.
"And it's terribly important to have new drugs for TB because we are getting more and more resistance.
"This is good, but it will be many years away and it must be tested very carefully."
Dr Mel Spigelman from the TB Alliance said: "We will need every one of these promising drug candidates if we are to conquer this complex global killer.
"A comprehensive solution to the TB pandemic will involve new combinations of totally novel drugs that are affordable and accessible for all those infected with TB, especially the two-thirds of the world's TB patients who do not have access to the best therapy today."
He said several other large pharmaceutical companies, including Novartis, GlaxoSmithKline and AstraZeneca, were devoting resources and expertise to the battle against tuberculosis.