Ali Kresge

Ali Kresge, global communications representative at Merck, said the company held trials for both sexes from the beginning but couldn't receive approval at the same time.

"The FDA wanted more expansive clinical trials," Kresge said.
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Kresge said the vaccine for both women and men was given in three dosages. The first one is given on a date chosen by the patient. Two months later the second dose is given. The final dose is given six months after the original date.
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Kresge said the side effects and overall safety of the vaccine were the same regardless of gender. She said the most common side effect was soreness at the injection site.

This is partially due to the fact that women are generally more health-conscious than men, says Ali Kresge, global communications spokeswoman at Merck Vaccines and Infectious Diseases.

"[Women] are proactive in their healthcare," Kresge says.