Gardasil: pros and cons

Gardasil: pros and cons

Frank Strehl

As I contemplated this month’s hot topics, I tried to think of the hottest topic facing today’s physicians, and I settled on Gardasil. It is true that when effective, it can prevent 70% of cervical cancers caused by the viruses that carry a high risk for becoming cervical cancer and is 90% effective against the viruses that carry a low to moderate risk for becoming cervical cancer (this type is generally responsible for genital warts). As I tell my students at National, my job is not to unduly influence their thought process or their decision for their patients but rather to provide them with the salient facts on which to base their decision. So, the question for you this month is, “Would you break from the profession’s tradition of opposing vaccinations and recommend this potentially life-saving vaccine for your patients and their daughters?”

Perhaps some of you would like a little more information about Merck’s Gardasil vaccine. The human papillomavirus (HPV) quadrivalent vaccine will be sold under the trade name Gardasil. It contains no live virus and is given in three separate intramuscular injections in the upper arm over a 6-month period. A Merck news release says that the vaccine will cost about $120 per dose–for a total of $360 for immunization. The actual cost to the physician is a little more than initially estimated.

The FDA emphasized to reporters that the product does not protect women if they have already been infected with HPV before vaccination. And yet, some gynecologists recommend and administer the vaccine to women with cervical dysplasia secondary to the HPV virus. Regulators say this fact “indicates the importance of immunization before potential exposure to the virus.” The product is also not designed to protect against less common HPV types, and routine Pap screening will therefore remain critical moving forward.

A background document provided to an FDA advisory committee flags a potential problem for a small subset of women. The briefing refers to the possibility that the HPV quadrivalent vaccine enhances disease among a subgroup of subjects with evidence of persistent infection with vaccine-relevant HPV types at baseline.

In the briefing document, the review team raises a second concern with cases of CIN 2/3 or worse from HPV types not included in the vaccine, “These cases of disease due to other HPV types have the potential to counter the efficacy results of Gardasil for the HPV types contained in the vaccine.”

The National Vaccine Information Center (NVIC) called on the CDC’s Advisory Committee on Immunization Practices (ACIP) to just say “no” on June 29 to recommending “universal use” of Gardasil in all preadolescent girls. NVIC maintains that Merck’s clinical trials did not prove the HPV vaccine designed to prevent cervical cancer and genital warts is safe to give to young girls.

The FDA allowed Merck to use a potentially reactive aluminum containing placebo as a control for most trial participants, rather than a non-reactive saline solution placebo. A reactive placebo can artificially increase the appearance of safety of an experimental drug or vaccine in a clinical trial. Gardasil contains 225 mcg of aluminum and, although aluminum adjuvants have been used in vaccines for decades, they were never tested for safety in clinical trials. Merck and the FDA did not disclose how much aluminum was in the placebo.

Animal and human studies have shown that aluminum adjuvants can cause brain cell death and that vaccine aluminum adjuvants can allow aluminum to enter the brain as well as cause inflammation at the injection site leading to chronic joint and muscle pain and fatigue. Nearly 90% of all Gardasil recipients and 85% of aluminum placebo recipients reported one or more adverse events within 15 days of vaccination, particularly at the injection site. Pain and swelling at injection site and fever occurred in approximately 83% of Gardasil and 73% of aluminum placebo recipients. About 60% of those who got Gardasil or the aluminum placebo had systemic adverse events including headache, fever, nausea, dizziness, vomiting, diarrhea, and myalgia. Gardasil recipients had more serious adverse events such as headache, gastroenteritis, appendicitis, pelvic inflammatory disease, asthma, bronchospasm and arthritis.

Merck and the FDA have not publicly revealed several important aspects of the trials:

* How many girls aged 9-15 participated in the clinical trials?

* How many of the participants received Gardasil and hepatitis B vaccine at the same time?

* How many of the participants experienced serious adverse events after injection of either Gardasil or the aluminum placebo?

For example, if fewer than 1,000 girls were actually injected with three doses of Gardasil, it is extremely important to know how many had serious adverse events and how long they were followed for chronic health problems, such as juvenile arthritis.

In May 2007, it was reported that over 1,600 adverse reactions, including three deaths, had been linked to Gardasil. Among those reactions, 371 were classified as serious, and of the 42 women who received the vaccine while pregnant, 18 experienced side effects including spontaneous abortion and fetal abnormalities.

It appears the number of reactions (and deaths) is steadily rising. A review of the National Vaccine Information Center revealed the following statistics about this vaccine: 2,207 adverse reactions to Gardasil have been reported including:

* 5 girls died

* 31 were considered life-threatening

* 1,385 required a visit to the emergency room

* 451 of the girls have not recovered as of July 2007

* 51 of the girls were disabled

Gardasil “may be more dangerous than consumers have been led to believe” according to one public interest group, and an editorial in the New England Journal of Medicine has also raised questions about the vaccine’s effectiveness.

It should be kept in mind that HPV types 6 and 11 are considered as low risk and are only two of approximately nine viral types in that group that can cause genital warts. Also, HPV types 16 and 18 are considered high risk for becoming cervical cancer and are only two of approximately 11 known to be in the group that are considered to be high risk for becoming cervical cancer.

Now, doctor, would your recommendation still be the same as when I asked the question at the beginning of this article? Perhaps it is time for us to take up our swords and fight this battle from the inside rather than from the outside of conventional medicine. Perhaps it is time for us to acquire a license to “unprescribe.”

by Frank Strehl DC, DABCI

COPYRIGHT 2007 Original Internist, Inc.

COPYRIGHT 2008 Gale, Cengage Learning