Breast Cancer Drug May Help Women Fight A Leading Cause Of Infertility: Study

A new study suggests women with PCOS (polycystic ovary syndrome) have a better chance of getting pregnant if they take a breast cancer drug instead of the currently preferred medication. PCOS affects 5 to 10 percent of reproductive-age women, according to background information in the study. Currently, typical prescription to boost fertility for women with PCOS is Clomiphene. However, this new study suggests the drug Letrozole results in better ovulation, conception and birth rates. "We found a simple and comparatively safe and vastly more effective treatment for polycystic ovary syndrome," said the lead researcher. Clomiphene, which works by stimulating ovulation, has been the standard treatment for years, but has a high rate of multiple births. Letrozole, a treatment for breast cancer in postmenopausal women, works by blocking estrogen production, tricking the ovaries into producing more of the hormone. Researchers found that almost 28% of the women taking Letrozole had babies after 5 cycles, compared with about 19% of those taking Clomiphene. Also, women taking Letrozole had fewer twin pregnancies, compared with those taking Clomiphene - about 3% versus 7%, the study found. "Clomiphene may be trumped," the researcher said. "To see a 40% improvement in birth rate is a huge difference." For the study, his team randomly assigned 750 women with PCOS to take Clomiphene or Letrozole. The drugs were given in five menstrual cycles with the dosage increased with each cycle. The overall ovulation rate was higher with Letrozole than with clomiphene – 62% compared to 48%. Clomiphene was associated with hot flashes, while some women using Letrozole reported fatigue and dizziness. For both drugs, birth defects were rare and rates were similar. “They were comparable with those seen in studies of women who conceive without treatment,” he claimed. “Whether Letrozole will cause more birth defects than other drug is not known,” the lead researcher stated, "we will need other studies to show that the rates of birth defects are actually low - lower than we would expect in an infertile population." Letrozole is relatively inexpensive, similar to the cost of clomiphene, so an affordable form of infertility treatment.

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 Study Links Vasectomy To Aggressive Prostate Cancer

Men who have a vasectomy may be at increased risk for aggressive prostate cancer, a new study suggests. But the risk is comparatively small, the researchers acknowledged. And several urologists not involved with the study said more research is needed to determine if the study findings are truly accurate. For the study, Harvard researchers analyzed data from more than 49,400 American men who were followed for 24 years, starting in 1986. During that time, 6,023 cases of prostate cancer were diagnosed among the men, including 811 fatal cases. The 25 percent of the men in the study who'd had a vasectomy had a 10 percent increased risk of developing prostate cancer, according to the study. Vasectomy was not linked with an increased risk of low-grade prostate cancer. But it was associated with a 20 percent higher risk of advanced prostate cancer and a 19 percent greater risk of fatal prostate cancer, respectively, the study authors said. Even among men who had regular prostate-specific antigen (PSA) screening tests for prostate cancer, those who had a vasectomy were 56 percent more likely to develop fatal prostate cancer. This link was strongest among men who had a vasectomy at a younger age. However, the absolute risk of developing deadly prostate cancer was small, the study authors noted -- 16 of every 1,000 men. "This study follows our initial publication on vasectomy and prostate cancer in 1993, with 19 additional years of follow-up and tenfold greater number of cases. The results support the hypothesis that vasectomy is associated with an increased risk of advanced or lethal prostate cancer," study co-author said. About 15 percent of men in the United States have a vasectomy. Prostate cancer is the second leading cause of death among American men, although most men diagnosed with the disease don't die from it. "The decision to opt for a vasectomy as a form of birth control is a highly personal one and a man should discuss the risks and benefits with his physician," study co-author said. The Harvard researchers said they were able to compensate for factors such as more frequent visits to doctors before reaching their conclusions.

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Dengue Fever Vaccine Shows Some Promise In Trial

A potential vaccine to protect children from the worldwide scourge of dengue fever was somewhat successful in a trial among Asian children. While the vaccine only prevented dengue fever in 56 percent of the 10,000 kids who got the full series of three shots, it protected more than 88 percent of them from severe disease. In the worst-case scenarios, dengue fever can lead to hospitalization, and sometimes death. "This vaccine has already proven to be safe," said an epidemiologist in the dengue branch of the U.S. Centers for Disease Control and Prevention, who had no role in the trial. "We know that this vaccine does not lead to a risk of developing severe dengue -- that is a huge step forward." However, "the 56 percent is not as high as we would like to see it. It's still a big step forward, but we have a way to go before we get a vaccine that is both safe and as efficacious as we would need it to be," epidemiologist added. The trial focused on children aged 2 to 14. They were randomly assigned to receive three injections of the CYD-TDV vaccine or a placebo vaccine. After the first vaccination, the second was given six months later and the third six months after that. The children were followed for up to two years. More than 28 days after the third vaccination, 117 children who received the vaccine developed dengue, compared with 133 who were given placebo. That works out to a vaccine effectiveness rate of 56.5 percent, the researchers noted. In addition, after three doses, the vaccine was 88.5 percent effective against severe disease, which often leads to hospitalization for over 500,000 people -- mostly children -- every year. "One of the difficulties in making a dengue vaccine is that you have to cover for four different viruses at the same time," epidemiologist explained. "If you are not able to do that, you risk increasing the chances of developing severe dengue." The vaccine wasn't equally effective against all four dengue viruses. It was only 35 percent effective against type 2, more than 75 percent effective against types 3 and 4, and 50 percent effective against type 1. The vaccine was well tolerated, the researchers reported. A total of 402 serious adverse events were reported in the vaccine group and 245 were reported in the placebo group.

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New Products of SQUARE Pharmaceuticals Ltd.

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