Drugs Are Found to Block HIV In Monkeys

The Truvada pill, made by Gilead Sciences, contains two antiretroviral drugs and was tested on monkeys in a scientific study. (By Paul Sakuma -- Associated Press)

Pills, Gel May Help Protect Women

By David Brown
Washington Post Staff Writer
Tuesday, February 10, 2009; A02

AIDS researchers who were gathered in Montreal yesterday heard encouraging results from studies of three strategies for preventing HIV infection using pharmaceuticals, particularly in women.

Two experiments in monkeys showed that antiretroviral (ARV) drugs, given by mouth or by vaginal gel, were highly effective in blocking infection by the virus that causes AIDS.

A third study, in 3,100 women in the United States and Africa, showed a small amount of protection from a vaginal gel that acts by binding up the AIDS virus and preventing it from invading cells.

Many experts believe that, short of a vaccine, a virus-blocking substance that could be inserted in the vagina or rectum before sexual activity would be the most important tool in fighting the AIDS pandemic. Numerous topical microbicides have been tried, but none have worked, and two have actually increased the risk of infection.

"The field of microbicide gels is now moving into a new generation," said Walid Heneine, a virologist at the U.S. Centers for Disease Control and Prevention, who led one of the monkey studies.

Microbicides can be applied without the knowledge of sexual partners. They are seen as being especially important in cultures where the subservient status of women makes it difficult for them to insist on abstinence or condom use, the two proven methods of preventing infection through sexual contact. In sub-Saharan Africa, nearly 60 percent of HIV-positive people are women.

The gel used in the human study reduced the risk of infection by 30 percent over the course of about two years, an effect that did not reach the level of statistical significance. The women -- from the United States, South Africa, Malawi, Zambia and Zimbabwe -- also used condoms in about three-quarters of their sexual encounters.

A study by British and African researchers that is testing the same microbicide in 9,400 women may have interim results later this year.

Although this result was marginal, the substance, called PRO 2000/5, may ultimately prove useful to women who are monogamous, are married to high-risk men and do not want to use condoms because they want to conceive, the lead researcher said.

"This could be a niche product for a group of women who have no other option," said Salim Abdool Karim of Durban, South Africa. He spoke at a news conference at the 16th Conference on Retroviruses and Opportunistic Infections, the annual mid-winter AIDS meeting in North America.

In the first monkey study, researchers gave rhesus macaques oral doses of a compound containing two ARV drugs, tenofovir and emtricitabine (which is sold under the name Truvada). The medicine was administered at different intervals, both before and after the animals were rectally exposed to the AIDS virus once a week for three months.

When the first dose was given either one or three days before contact with the virus, five out of six animals were protected. When it was given seven days before exposure, four in six animals were protected. When the dose was two hours before exposure, however, only three in six were protected.

Of 27 untreated animals, 26 became infected after an average of two exposures.

Tenofovir has a very long active life inside the body. But two hours appears to be not enough time for it to be absorbed and carried into the cells of the immune system, which are HIV's target, said J. Gerardo García-Lerma, the CDC virologist who led the study.

There are seven studies in people testing either Truvada or tenofovir alone as an HIV-prevention pill. In each of the experiments, which are enrolling a total of 18,000 volunteers in the United States, Kenya, Uganda, Botswana and Thailand, the drugs are administered every day. The monkey study suggests that intermittent dosing might work, too.

In the other monkey study, researchers used vaginal gels containing either both drugs or tenofovir alone. The gel was applied half an hour before twice-weekly vaginal exposure to the virus.

The six monkeys that received the two-drug gel were all protected, as were the six who got the tenofovir-only gel. Of 11 monkeys in a control group, 10 became infected after an average of four exposures to the virus.

Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, said he was buoyed by the results of the animal experiments and not entirely discouraged by the human results.

"In such a sea of disappointment as microbicide research, a study that is even a little encouraging is something to notice," he said.

Ecstasy 'not worse than riding'

The panel will review the latest evidence before making its decision

Taking the drug ecstasy is no more dangerous than riding a horse, a senior adviser has suggested.

Professor David Nutt, chairman of the Advisory Council on the Misuse of Drugs (ACMD), outlined his view in the Journal of Psychopharmacology.

The council, which advises the government, is expected next week to recommend that ecstasy is downgraded from a class A drug to a class B one.

Ministers have outlined their opposition to any such move.

Professor Nutt wrote: "Drug harm can be equal to harms in other parts of life. There is not much difference between horse-riding and ecstasy."

Organ failure

The professor said horse-riding accounted for more than 100 deaths a year, and went on: "This attitude raises the critical question of why society tolerates - indeed encourages - certain forms of potentially harmful behaviour but not others such as drug use."

Professor Nutt's academic work does not prejudice that which he conducts as chair of the ACMD ACMD spokesman

Ecstasy use is linked to around 30 deaths a year, up from 10 a year in the early 1990s. Fatalities are caused by massive organ failure from overheating or the effects of drinking too much water.

The ACMD last night distanced itself from Prof Nutt's comments.

A spokesman for the body said: "The recent article by Professor David Nutt published in the Journal of Psychopharmacology was done in respect of his academic work and not as chair of the ACMD.

"Professor Nutt's academic work does not prejudice that which he conducts as chair of the ACMD."

'No safe dose'

David Raynes, of the National Drug Prevention Alliance, told the Daily Telegraph: "He is entitled to his personal opinion, but if his personal view conflicts so very strongly with his public duties, it would be honourable to consider his position.

"If he does not, the home secretary should do it for him."

Last September a Home Office spokesman said the government believed ecstasy should remain a Class A drug.

"Ecstasy can and does kill unpredictably. There is no such thing as a 'safe dose'," he said.

Breakthrough drug restores white hair to its original color

By Fiona Macrae

In a discovery that could brighten up the lives of millions, scientists have created a drug that restores white hair to its natural colour.

They hope the drug, converted into a shampoo, could eventually be used as an alternative to dyes to hide greying locks.

The drug was found to trigger the production of pigmentation in hair samples tested in a lab.

Miracle cure: Scientists are working on a drug which reverts hair to its original colour

These pigments restored the hair to its original colour, from the white or grey it had become.

This took place no matter what the hair colour was to begin with.

The drug, known only as K(D)PT, increased pigmentation when it was applied to hairs gleaned from women undergoing facelifts.

However, it was effective only when the strands had been pre-treated to mimic the damage found in conditions that cause hair loss, including some forms of alopecia.

In such conditions, hair that grows back is often white.

Researcher Dr Ralf Paus, of the Manchester University and the University of Lubeck in Germany, said the drug ‘deserved to be explored as an innovative new anti-greying agent’.

Writing in the British Journal of Dermatology, he added: ‘Specifically, topical application of K(D)PT may become exploitable for the treatment of post-inflammatory hair whitening that is often seen during the recovery phase of alopecia areata.’

Nina Goad, of the British Association for Dermatologists, described the study as ‘an important step’.

She added: ‘It is important to note this is laboratory research and not yet ready for use on patients.

‘However, while the research is still at a very early stage, these findings could potentially pave the way for new therapies that restore colour to white hair.’

Back to his roots?: Using the new drug, TV presenter Phillip Schofield could turn his white hair back to dark brown

The researchers believe there is also ‘a reasonable possibility’ that hair turned grey by ageing would also respond.

The preliminary nature of the work means it is not possible to say if the drug would fully restore hair to its natural colour, although this could well be the case.

It is likely the treatment, which would have to be reapplied regularly, would work for men and women.

The synthetic hormone in the drug could only be used on lab hair samples. It is not yet ready to be applied directly to a patient’s head.

Fountain of Youth: Drug Restores Muscles

By LiveScience Staff

A daily dose of an investigational medication has been found to restore muscle mass in the arms and legs of older adults and improve some of their biochemistry to levels found in healthy young adults, suggesting an anti-frailty drug has been found.

The drug, called MK-677, was evaluated for its safety and effectiveness in a study that showed the drug restored 20 percent of muscle mass loss associated with normal aging. In fact, levels of growth hormone (GH) and of insulin-like growth factor I (IGF- I) in healthy seniors who took the drug increased to the levels found in healthy young adults, said Michael O. Thorner, a professor of internal medicine and neurosurgery at the University of Virginia Health System.

"Our study opens the door to the possibility of developing treatments that avert the frailty of aging," Thorner said. "The search for anti-frailty medications has become increasingly important because the average American is expected to live into his or her 80s, and most seniors want to stay strong enough to remain independent as they age."

Funded by the National Institutes of Health, the two-year, double-blind, placebo-controlled study involved 65 men and women ranging in age from 60 to 81. The results are detailed in the Nov. 4, 2008, issue of the journal Annals of Internal Medicine.

The drug mimics the action of ghrelin, a peptide that stimulates a growth hormone called secretagogue receptor (GHSR). Drug developers are focusing on GHSR because it plays an important role in the regulation of growth hormone and appetite. They think it may prove to be an excellent treatment target for metabolic disorders such as those related to body weight and body composition.

Drugs found to work in early trials don't always hold up to further testing, however.

The new research was a "proof-of-concept" study that sets the stage for a larger and longer clinical trial to determine whether MK-677 is effective in people who are frail and to assess its long-term safety.