Merck, maker of the cervical cancer vaccine Gardasil, is backing off its lobbying campaign following pressure from medical groups and parents who believe the vaccine should not be mandated as a school attendance requirement for adolescent girls.

The public outcry that caused Merck to announce its stop order on Tuesday stems from the fact that the vaccine protects against the sexually transmitted human papilloma virus (HPV), which causes cervical cancer. School-mandated vaccines are typically for diseases spread through casual contact, such as measles and mumps.

Merck's medical director for vaccines, Dr. Richard M. Haupt says, "We're concerned that our role in supporting school requirements is a distraction from that goal, and as such have suspended our lobbying efforts," adding that the company will continue providing information about the vaccine upon request.

Gardasil, launched in June and the first vaccine to prevent cervical cancer, has inspired controversy since day one. There's the cost -- $360 for three required shots -- and all sorts of insurance concerns and conservative groups who worry the vaccine encourages premarital sex and interferes with parental rights. Even those in support of the vaccine -- like the American Academy of Pediatrics and the American Academy of Family Practitioners -- question Merck's quick push to market this drug, especially in light of the company's withdrawn painkiller Vioxx.

"I believe that their timing was a little bit premature so soon after (Gardasil's) release, before we have a picture of whether there are going to be any untoward side effects," says Dr. Anne Francis, who chairs an American Academy of Pediatrics committee.

Legislatures in 20 states have taken steps to mandate the vaccine for young girls. And with the exception of Texas governor Rick Perry's February 2 executive order requiring Texas girls entering the sixth grade in 2008 get vaccinated, nothing has been made official so far.

The Mayo Clinic Cancer Center has opened a new clinical study today using a vaccine strain of the measles virus to attack recurrent glioblastoma multiforme (GBM). The Mayo Clinic's research has grown from the most basic laboratory science to the sophisticated therapy being tested today on several tumor types, including GBM, recurrent ovarian cancer and multiple myeloma.

The study is designed to test the safety of the virus for the treatment of gliomas and enable monitoring of anti-tumor activity. Eligible candidates for the therapy will have GBM that has progressed after surgery and radiation therapy. They also must be immune to measles, either having had the disease or been vaccinated against it.

Many cancer cells, including glioblastoma cells, overexpress a specific protein which allows tumor cells to avoid destruction by the immune system. Strains of the measles virus seek out this protein and enter the tumor. When it enters the virus begins to spread infecting nearby tumor cells which increases cancer cell death.

Back in the1970's it was noted that measles infections could cause regression of cancer tumors in children. Nothing was done about studying this phenomenon until late in the 1990's when the Mayo Clinic Cancer Center's Molecular Medicine Program began looking into it. The researchers are now also looking at ways to use the measles virus to combat breast and pancreatic cancer, they already have plans to open up another clinic study this fall to test the effectiveness of a version of the measles virus on multiple myeloma.