About The Study

The NOVA-HIV Study (CTN 339) is assessing whether two doses of the human papillomavirus (HPV) vaccine produce a similar immune response in women living with HIV compared with the traditional three-dose schedule. Data supporting a reduced dosing schedule will inform Canadian and global public health recommendations and may improve HPV vaccination programming in low- and middle-income countries with a high prevalence of HIV.


In Canada, one woman dies every day from cervical cancer. Worldwide, it is the fourth leading cause of cancer-related death in women, and the primary cause of cancer-related death in women in low- and middle-income countries. Cervical cancer disproportionately affects marginalized populations, including Indigenous women and women living with HIV (WLWH). Almost all cases of cervical cancer are caused by HPV, and WLWH are more vulnerable to HPV infection and persistence: North American WLWH have twice the prevalence of HPV infection and four-fold higher rates of invasive cervical cancer compared with HIV-negative women.

In the early 2000s, many countries launched three-dose HPV vaccine programs. Because they are so effective, programs have since been reduced to two doses and, most recently, the World Health Organization recommends one dose programs. While research, including results from CTN 236, shows that three doses of the older generation of HPV vaccines are safe and effective in WLWH, it is unknown whether a reduced dosing schedule of the newer vaccine formulation is effective in WLWH. Reducing the dosing schedule for WLWH would greatly increase the feasibility of HPV vaccination programs for these women, including the 600 Canadian women who are diagnosed with HIV each year. This population is most in need of protection and is critical to achieving cervical cancer elimination around the world.

Study Approach

The overall goal of this study is to assess whether two doses of HPV vaccine produce a comparable immune response to three doses. Four-hundred and fifty participants will be enrolled at clinics in Vancouver, Regina, Winnipeg, Toronto, Hamilton, Montreal, and Québec City. Participants will be randomized to receive three doses of HPV vaccine, either at the regular schedule of zero, two, and six months or at an extended schedule of zero, six, and 12 months. Both groups will attend seven study visits over two years where they will undergo routine blood work and clinical exams, including regular HIV care. Analyzing data collected at the various intervals, the research team will compare the immune response between participants who received a different number of doses.

Eligibility Requirements

Inclusion Criteria:

  1. Living with HIV
  2. Has a cervix (not having had their uterus removed)
  3. Aged 18–45 years
  4. Willing to avoid pregnancy while the vaccine is being given
  5. Able to communicate in English if adequate translation is not available

Not Allowed

  1. Unable to give fully informed consent
  2. Allergy to the vaccine or its components
  3. Prior receipt of any HPV vaccine

Additional Information

If you would like to take part in this study or want more information, please contact:

Dr. Elisabeth McClymont
Postdoctoral Fellow, University of British Columbia

Principal Investigator

Here’s who is leading this study.

Can’t find what you’re looking for? Email ctninfo@hivnet.ubc.ca.

Participating Sites

Here’s where this study is being conducted.

Oak Tree Clinic, BC Women’s Hospital

Vancouver, BC

Dr. Deborah Money
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Centre Hospitalier de l’Université de Montréal (CHUM)

Montreal, QC

Dr. Isabelle Boucoiran
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Centre Hospitalier de l’Université Laval

Québec City, QC

Dr. Marie-Louise Vachon
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