Canadian Government on Gardasil

 

In the HOC

Government Contracts
Oral Questions

April 17th, 2007 / 3 p.m.

NDP

Penny Priddy Surrey North, BC

Mr. Speaker, every time the Conservatives talk about health, Canadians are left with more questions than answers. A lot of people are asking if the $300 million exclusive contract was awarded to Merck Frosst for the HPV vaccine because a Conservative lobbyist who used to work for the Prime Minister was on the file.

The Canadian Revenue Agency says Merck used tax havens in the Barbados to hide profits. The IRS in the United States is also investigating Merck for back taxes. Why is this government giving Merck millions of dollars and not collecting the billions owed to Canadian–

Government Contracts
Oral Questions

3 p.m.

Liberal

The Speaker Peter Milliken

The hon. Minister of Finance.
Jim Flaherty Minister of Finance

Mr. Speaker, we are very proud to take a step in the budget to support this vaccine for women and girls across Canada. It is the first vaccine that can actually prevent cancer. This is an important step forward.

I was pleased to be at the Ottawa Hospital yesterday, at the Shirley Green centre for women’s health, to make the announcement. This is an important step forward. There is one vaccine available now. Another manufacturer is developing another one.

The important thing is that thousands of Canadian women and girls will not die from cancer because of this vaccine’s availability.

Penny Priddy Surrey North, BC

Mr. Speaker, a cancer vaccine is very important for women, but why in this case is the government letting big corporations out of paying their fair share? Why is the Minister of Health rewarding a company that has evaded $2 billion in Canadian taxes?

I am not sure if Conservative staffer turned pharma lobbyist Ken Boessenkool was the reason Merck got the money, but I do know that Merck owes Canadian taxpayers over $2 billion. Did the minister meet with Boessenkool? Did the minister consider the issue of the tax havens when making his decision?

Jim Flaherty Minister of Finance

No, Mr. Speaker, I did not meet with Mr. Boessenkool on the subject.

I can say that I met with Liz Ellwood yesterday at the hospital. She is a 24-year-old victim of the papillomavirus, HPV. She has suffered from it and she said thanks to me on behalf of the women and girls in Canada and to this government and this Prime Minister for supporting the availability of this vaccine across Canada.

Paul Dewar Ottawa Centre, ON

Mr. Speaker, today in question period one of our members asked a question of the Minister of Finance regarding the loopholes that were evident in the back taxes that were not paid by a certain corporation.

In his response, the minister mentioned visiting the Shirley Green hospital yesterday. I just want to correct that for the minister. It is the Shirley Greenberg hospital. She is a well-known member of our community and I just wanted to clear the record for him.

——————————————————————————————————————————————————————————-

The Government of Canada’s statement on Gardasil Safety

Recommendations on a Human Papillomavirus Immunization Program

3. HPV vaccine characteristicsTwo HPV vaccines have been tested in clinical studies: GardasilTM, by Merck Frosst, and CervarixTM, by GlaxoSmithKline. The quadrivalent vaccine GardasilTM, which contains HPV types 6, 11, 16 and 18, was authorized for sale in Canada for females between 9 and 26 years of age in 2006. The bivalent vaccine CervarixTM, which contains HPV types 16 and 18, has been submitted for approval. CervarixTM includes a new adjuvant, AS04, which contains monophosphoryl lipid A, derived from bacterial cell walls and alum.

GardasilTM and CervarixTM are subunit vaccines containing virus-like particles produced by recombinant technology. The vaccines cannot cause disease because they contain no live biologicals or DNA and are not infectious. They have been shown to be safe and generally well tolerated(11-14): in clinical trials, systemic adverse events such as headache or fatigue were reported by a similar proportion in the vaccine and placebo recipients(2).

In clinical trials, the vaccines showed a remarkable 90%-100% efficacy against the development of high-grade cervical lesions associated with HPV 16 and 18 for periods of up to 5.5 years.

Immunogenicity data are available for women aged 9-26 and boys aged 9-15 vaccinated with GardasilTM and for women aged 10-45 vaccinated with CervarixTM(15-18). One month following the administration of the third dose, nearly all participants (= 99%) had developed antibodies against the types of HPV contained in the vaccines. The antibody levels after vaccination have been found to be 10-100 times higher than the levels produced by natural infection. Comparative studies have shown that the average anti-HPV geometric mean titres (GMTs) in preadolescents and adolescents aged 9-14 were twice those in women aged 15-25(16). One month after the second dose of GardasilTM, GMTs against all virus types included in the vaccine in youths aged 10-15 were higher than the GMTs observed 1 month after the third dose in women aged 16-23(16). The vaccine was well tolerated in both age groups.

The seroconversion rate 1 month after the second dose exceeded 97.5% for all types of HPV included in the vaccine(16). Robust anti-HPV GMTs were observed at this time.

Efficacy data are not available for the 9-13 age group since most are not sexually active and pelvic examinations are not performed and that CIN does not develop at such a young age. However, immunogenicity results showing high antibody response in young girls would support no inferiority in protection as compared with older age groups.

A recent double-blind, placebo-controlled study examined the extent of immune memory in response to a primary vaccination series with a quadrivalent HPV vaccine. Serum anti-HPV levels declined after vaccination but reached a plateau at month 24 and remained stable through month 60. Administration of a challenge dose of vaccine induced a classic anamnestic response, with anti-HPV levels 1 week post-challenge reaching levels observed 1 month after completion of the three-dose primary series. At 1 month post-challenge, anti-HPV responses were higher than those observed 1 month after the third dose. The authors concluded that HPV vaccine induces high efficacy and stable anti-HPV levels for at least 5 years(19).

The main criteria used in clinical trials to establish the efficacy of the vaccines were as follows:

  • a reduction in the number of moderate and severe abnormalities (CIN 2/3) and adenocarcinoma in situ; and
  • a reduction in the incidence of persistent infections with the types of virus included in the vaccine(20).

Cervical cancer has not been used as the primary criterion for measuring the efficacy of HPV vaccines in clinical trials because of the time it takes for the disease to develop and the need for appropriate clinical management of premalignant lesions to be provided immediately(21).

Aside from the prevention of lesions caused by HPV 16 and 18, CervarixTM has been shown to be 35% to 60% effective in preventing infections caused by types 31 and 45, which are responsible for 8%-10% of cervical cancers(15,22). Cross-protection data on GardasilTM are emerging. GardasilTM has also been shown to provide 99% protection against anogenital condylomas in women.

There is no evidence that women who have already been infected with one of the types contained in a vaccine will be protected against that type by vaccination. This is why it is preferable to vaccinate girls before the onset of sexual activity. Currently, there are no data on the efficacy of the vaccines in men or on the interchangeability of the two HPV vaccines.

Manufacturers currently recommend a schedule of three doses administered at 0, 2 and 6 months for GardasilTM or 0, 1 and 6 months for CervarixTM. A clinical trial was started in 2007 to determine the immunogenicity of a schedule of two doses of GardasilTM spaced 6 months apart in girls aged 9-13 compared with three doses given to young women aged 16-26. The study, involving 825 girls, is funded by the ministries of health of British Columbia, Quebec and Nova Scotia(23). A clinical trial is also planned to determine the immunogenicity of a two-dose schedule with CervarixTM.

HPV vaccines are safe and well tolerated. Clinical trials have found no increased number of serious adverse events in girls/women who received HPV vaccine compared with those who received placebo, and the types of serious adverse event reported were similar in the vaccine and placebo groups. There was no evidence that vaccination resulted in allergic reactions or other immune-mediated disease(2). As of 30 June, 2007, 13 cases of possible Guillain-Barré syndrome (GBS) after vaccination with GardasilTM had been reported in the United States with distribution of more than 7 million doses. Expert review indicated that only two out of the 13 met the case definition of GBS. These two cases occurred within 6 weeks of vaccination with GardasilTM alone. Because GBS occurs at a rate of 1-2/100,000 person-years during the second decade of life, 13 reported cases of GBS are within the expected numbers(24).

Additional information on HPV vaccines can be found in the NACI Statement on Human Papillomavirus Vaccine(2).

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s