Bionor Pharma ASA, the Norwegian developer of an experimental AIDS treatment, said the injection lowered viral levels in patients’ blood and helped some of them stay off daily pills for more than a year.
As many as 30 percent of patients in a study of Bionor’s Vacc-4x were able to stay off antiretroviral therapy more than a year after they stopped, compared with 18 percent who got a placebo, the Oslo-based company said in a statement today. The results were presented at a conference in Bangkok.
The findings may help Bionor revive Vacc-4x after saying in October it would scrap the shot because six-month data showed it didn’t work, sending the stock down 81 percent. A month later the company reversed the decision after further analysis showed the treatment lowered viral levels. It now plans three more trials to see if it can improve on today’s results, including one combining Vacc-4x with Celgene Corp.’s cancer drug Revlimid.
“We don’t see this as a standalone alternative to antiretroviral therapy,” Vidar Wendel-Hansen, Bionor’s chief medical officer, said in an interview. “What we do see is the long-term potential to train the immune system to take over the role of antiretroviral therapy. That’s the goal.”
Bionor was unchanged at 1.55 kroner at the close of trading in Oslo.
‘Not as Compelling’
Unlike the pills that are the mainstay of HIV treatment, Vacc-4x is a so-called therapeutic vaccine designed to fight the virus by marshaling the body’s immune system against it. While the shot hasn’t yet been shown to subdue the virus as well as antiretroviral therapy, regular injections that keep it at relatively low levels may save patients from the side effects and costs associated with pills.
The trial involved 135 patients who had been using anti-AIDS drugs to control HIV for at least six months. Two-thirds received six shots of Vacc-4x while taking their regular pills over 28 weeks, then stopped taking the drugs. The other third received an injection of water.
Six months later, those who got the shot had an average 70 percent reduction in the amount of virus in their blood compared with the level before they started pill therapy. More than a year after they went off treatment, 30 percent of them remained pill-free, compared with 18 percent of the placebo group.
“Several years ago I would have been tremendously excited” by the results, Michael Saag, director of the Center for AIDS Research at the University of Alabama at Birmingham, said in an e-mail.
“Now I find it interesting, but not as compelling,” Saag said. “The reason is that we have growing evidence that, even with no detectable virus among folks not on antiretroviral therapy, there is evidence of increased inflammation.” Even low levels of viral replication -- which the pills control -- could be harmful to patients in the long-term, according to Saag.