The drug, called EMA401, targets a different pain mechanism to existing treatments and appears to have fewer side effects.
The Shingles Support Society has welcomed the study results as a "positive development."
Researchers from Imperial College London also hope that the drug could also be effective for other chronic neuropathic pain, caused by diabetes, HIV, nerve injury and chemotherapy cancer treatment, for example.
The new drug EMA401 is known as a highly selective angiotensin II type 2 receptor antagonist (AT2R). It was trialled on 183 patients with postherpetic neuralgia in 6 countries with those taking part taking 2 tablets a day for 28 days. Around half the patients took the new drug, the rest were given a placebo or dummy treatment.
The study found that 58% of those taking the new drug found it to be effective, reducing pain by at least 30%.
The study, published in the Lancet, did not report any serious side effects.
In a statement, the lead author of the study Professor Andrew Rice, from the Department of Surgery and Cancer at Imperial College London, says: "A positive trial like this in such a challenging condition as post-herpetic neuralgia, for a drug that acts in a new way, is unusual and very exciting. We hope that the new drug will ultimately offer hope for patients who aren't helped by current treatments."
Larger trials are now being planned to confirm the study's findings. The research was funded by the pharmaceutical company that's developing EMA401.
In a comment article linked to the study, Nanna Brix Finnerup and Cathrine Baastrup from the Danish Pain Research Center, Aarhus University, write that: "It is reasonable to postulate that AT2R antagonists could also be effective in other neuropathic pain disorders, such as peripheral nerve injury and chronic inflammatory pain."
In a statement, Marian Nicholson from the Shingles Support Society says: "This is a positive development and we very much welcome it. Research carried out so far seems to indicate that the treatment is safe, so we hope that new trials with higher doses can make it even more effective.
"Shingles pain, or PHN mainly affects the elderly. It can render a patient's final years an unendurable misery. Prompt treatment may help to prevent this, so we urge anyone who thinks they may have shingles to go to the doctor immediately."
Lancet: A.S.C. Rice et al. 'EMA401, an orally administered highly selective angiotensin II type 2 receptor antagonist, as a novel treatment for postherpetic neuralgia: a randomised, double-blind, placebo-controlled phase 2 clinical trial.' The Lancet, 5 February 2014
Lancet comment: Nanna Brix Finnerup and Cathrine Baastrup from the Danish Pain Research Center, Aarhus University
Imperial College London news release
Shingles Support Society
To provide even greater transparency and choice, we are working on a number of other cookie-related enhancements. More information