Health Rounds: Hormone named for iconic chocolate treat may boost sexual desire

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Feb 7 (Reuters) -

Welcome to Health Rounds! Today we report on data from two small early trials in which the naturally-occurring hormone kisspeptin showed promise for treating low sexual desire. Also, researchers reported this week that rates of potentially deadly whooping cough in very young infants have come down since health officials started advising pregnant women to get vaccinated. And a study published on Tuesday that finds that pharmaceutical companies are spending the most on direct-to-consumer ads to sell us drugs with comparatively smaller benefits.

Hormone named for chocolate candy might boost sexual desire

Kisspeptin, a naturally-occurring hormone that stimulates the release of other reproductive hormones in the body, may prove useful for treating low sexual desire, two preliminary studies suggest.

The gene for kisspeptin was discovered by researchers in Hershey, Pennsylvania, who named it after the iconic chocolate ‘Kisses’ made there by Hershey Co.

In a trial involving 32 men published on Friday in JAMA Network Open and a separate trial involving 32 premenopausal women published in the same journal in October, a single intravenous infusion of kisspeptin had positive effects on sexual responses, researchers reported.

The study participants all had hypoactive sexual desire disorder (HSDD), or low sexual desire that is distressing to the individual. There are currently no effective drugs for HSDD.

The researchers had previously shown that kisspeptin can enhance responses to sexual stimuli and boost attraction brain pathways in men with healthy sexual desire.

In the new studies, the researchers employed blood tests, hormonal measurements, behavioral analyses and magnetic resonance imaging of the brain to investigate the effect of kisspeptin on responses to erotic videos in women and men with low sexual desire. Participants each received the hormone and a placebo, on two separate occasions.

In men, kisspeptin affected brain activity in key structures of the sexual-processing network and led to increased sexual behavior and erection in response to the videos, the researchers said. Placebo did not have a similar effect.

In women, the treatment restored sexual and attraction brain processing, according to the study authors.

“It is highly encouraging to see the same boosting effect in both women and men, although the precise brain pathways were slightly different as might be expected,” coauthor Waljit Dhillo of Imperial College London said in a statement.

Kisspeptin was well-tolerated with no reported adverse side effects.

“Our two studies provide proof-of-concept for the development of kisspeptin treatments, as we provide the first evidence that kisspeptin is a potentially safe and effective therapy for both women and men with distressing low sexual desire,” Alexander Comninos, also of Imperial College London, said in a statement.

Drugmakers spend more on ads for less effective treatments

Pharmaceutical companies spend more money trying to sell drugs that confer limited benefits to patients than they do on direct-to-consumer (DTC) ads for highly effective drugs, according to a study published on Tuesday in JAMA.

Drug company spending on consumer messaging in magazines, newspapers, billboards, radio, digital platforms and television does pay off with higher sales, the study found.

Researchers analyzed data available for 134 of the 150 top-selling prescription drugs in the United States in 2020. The average spend on advertising that year was $20.9 million per drug, with 13.5% of that total allocated to direct-to-consumer ads.

The United States, one of the only developed nations with DTC prescription drug advertising, does not assess medicines for comparative effectiveness, so researchers used French and Canadian government ratings of the same top-selling drugs. Nearly 70% were rated as offering low added benefit.

The average proportion of promotional DTC spending was 14.3% higher for drugs deemed to provide low added benefit than for those rated as highly beneficial.

For 12 of the top-selling drugs, more than 80% of promotional spending went to ads for consumers. Seven of those drugs were rated as low-benefit.

The average sales per drug in 2020 was $1.51 billion. But every 1.5% increase in DTC spending was linked with a 10% increase in total sales, researchers found.

DTC ad spending “reflects a strategy to drive patient demand for drugs that clinicians would be less likely to prescribe,” study leader Michael DiStefano of the Johns Hopkins Bloomberg School of Public Health said in a statement.

Whooping cough vaccine in pregnancy protects newborns

The practice of vaccinating pregnant women against whooping cough, or pertussis, has reduced the number of cases in babies who are not old enough to get the vaccine themselves but are most vulnerable to the illness that can be deadly to them, according to new data.

In 2011, U.S. health officials started recommending pregnant women receive the Tdap vaccine, which protects against tetanus, diphtheria, and pertussis.

After a woman receives Tdap, her body creates protective antibodies and passes high levels of them to her baby before birth. These antibodies provide the baby with some short-term protection against whooping cough in early life, according to the U.S. Centers for Disease Control and Prevention (CDC).

For a study reported on Monday in JAMA Pediatrics, CDC researchers calculated and compared pertussis rates in more than 57,000 infants younger than 1 year before and after doctors started to recommend the vaccine in pregnancy.

From 2012 to 2019, the pertussis rate in babies younger than 2 months declined, compared to what it had been from 2000 to 2010 prior to the recommendation.

By 2017-2019, the pertussis incidence in these youngest babies had stabilized at 80.9 per 100,000 infants, down from 165.3 per 100,000 infants during the pre–maternal Tdap vaccination period, according to the report.

The rate of pertussis in the older babies held steady.

“These findings suggest that maternal Tdap vaccination is associated with a reduction in pertussis among infants younger than 2 months, the strategy’s target age group,” the researchers said.

As of 2019, just 55% of pregnant women were getting the vaccine. Bringing that number up might achieve additional reductions in infant disease, the researchers added. (Reporting by Nancy Lapid; Editing by Bill Berkrot)