LONDON – GlaxoSmithKline (NYSE: GSK) and Johnson & Johnson are preparing to test the first monthly injections of experimental AIDS drugs in a study that may transform the treatment of the deadly disease.

The study will build on the drugs’ success as a combination of daily pills when pitted against Bristol-Myers Squibb Co.’s Sustiva.

A trial showed that Glaxo’s GSK1265744 and J&J’s Edurant helped a higher percentage of patients than Sustiva when given with other drugs commonly used to control the virus, according to data presented today at a conference.

Once treated with as many as 30 tablets a day, HIV is now subdued with a once-daily pill such as Gilead Sciences Inc.’s Atripla. Glaxo released data Tuesday that showed its medicine may also prevent HIV infection when given once every three months. Long-acting AIDS drugs would alleviate the inconvenience and side effects of daily pill-taking, said Kenneth Mayer, medical research director of the Fenway Institute in Boston.

“These drugs are leading the way” toward longer-acting treatments, John Pottage, chief scientific and medical officer for ViiV Healthcare, the venture of London-based Glaxo, New York-based Pfizer Inc. and Osaka, Japan-based Shionogi & Co. that is developing GSK1265744.

The drug is a version of Glaxo’s Tivicay, which won U.S. regulatory approval in August.

New Brunswick, New Jersey-based J&J’s Edurant was approved in 2011.

A trial of monthly injections of the two drugs will start in the next few months, with results expected in 2016, Pottage said.

‘Deep Look’

“We’re taking a deep look at trying to accelerate things because there is an interest and a pull for this type of therapy,” Pottage said. It’s too early to say how big the market for long-acting drugs will be, but it will be “significant,” he said.

The trial data released today showed that 82 percent of patients taking GSK1265744 and Edurant had undetectable levels of HIV in their blood after 48 weeks, compared with 71 percent of those who took Sustiva, researchers said at the Conference on Retroviruses and Opportunistic Infections in Boston.

More than 80 percent of HIV-infected people said they would probably or definitely try monthly injectable therapy, according to a survey of 400 patients published last year in the journal Nanomedicine.

Glaxo also is studying GSK1265744 as a way of preventing HIV infection in people who don’t have the virus but are at risk, such as gay men. Results from tests of that approach in monkeys were presented Tuesday in Boston.

[GSK operates its North American headquarters in Research Triangle Park, N.C.]

[GSK ARCHIVE: Check out more than a decade of GSK stories as reported in WRALTechWire.]