This page provides information about the HPV vaccine, including safety and effectiveness.
What is in the vaccine?
The HPV vaccine used in the New Zealand Immunisation Programme from 2017 is Gardasil® 9. The vaccine contains HPV virus-like particles (VLPs) of HPV types 6, 11, 16, 18, 31, 33, 45, 52 and 58. These particles are proteins from the outer shell of the virus. The VLPs do not contain DNA fragments in a form that could allow them to infect cells or reproduce. The particles mimic the HPV virus so that the immune system makes antibodies against it. These recombinant types of vaccine have been used around the world for over 20 years.
Each 0.5ml dose of the vaccine also contains a small amount of aluminium, which stimulates the immune response. Aluminium has been safely and effectively used in vaccines for more than 70 years. The vaccine also contains tiny amounts of sodium chloride (salt), L-histidine (an amino acid), Polysorbate 80, sodium borate and sterile water.
The vaccine does not contain preservatives, antibiotics or any human or animal materials.
The Medsafe website has further information about Gardasil 9:
- Prescriber Update: Gardasil 9 – The Next Generation Human Papillomavirus (HPV) Vaccine
- Consumer Medicine Information
- Datasheet
Safety of the vaccine
Gardasil 9 was shown to have a good safety profile during large clinical trials in which more than 15,000 people took part. HPV vaccines are licensed for use in more than 125 countries, including New Zealand, Australia, the United Kingdom, the United States, Canada and the European Union.
In New Zealand, as in other countries, there is ongoing monitoring of vaccine safety.
All applications for consent to distribute a medicine in New Zealand are evaluated by Medsafe. This evaluation is performed to internationally defined standards and requirements. Gardasil 9 was evaluated by Medsafe and formal approval of the vaccine was notified in the New Zealand Gazette on 11 February 2016.
More information
Effectiveness of the vaccine
Gardasil 9 vaccine targets the types of HPV responsible for around 90 percent of cervical and other HPV-related cancers, and 90 percent genital warts. Clinical trials show it is highly effective in preventing these types of HPV in young people who have not previously been exposed to them.
So far, ongoing studies suggest protection will be long lasting, as is the case with the Hepatitis B vaccine.
History of the vaccine
Development
The link between HPV infection and cervical cancer was recognised in the 1980s. The doctor who discovered this link was awarded the Nobel Prize for Medicine.
Scientists have worked since then to develop a vaccine to protect against HPV infection. This work was started in the mid-1980s jointly by the University of Queensland (Australia), Georgetown University Medical Center (USA), the University of Rochester (USA), and the National Cancer Institute (USA).
Three vaccines have since been produced. One of the vaccines (Cervarix®) is not available in New Zealand. Another, the older Gardasil® vaccine, protected against four types of HPV and was used in New Zealand from 2008. Gardasil 9 replaces Gardasil in New Zealand in early 2017.
Testing
The clinical trials for the original HPV vaccine involved more than 20,000 women aged 16 to 26 from 33 countries, including clinical trials in New Zealand.
The trials showed the vaccine had almost 100 percent efficacy in preventing cervical abnormalities caused by high-risk HPV types 16 and 18. The trials did not allow cervical cancer to develop as an end-point – it would have been unethical to deny treatment to women in the placebo group.
For ethical reasons, younger girls were not included in some of the trials as they would have been required to have regular smear tests and other swabs, which would have been inappropriate given their age.
Instead immune response studies were used to compare the development of immunity from the vaccine between younger and older girls. These trials showed that immune responses were up to two-fold higher in girls aged 9 to 15 compared with those aged 16 and over; that is, they responded as well if not better to the vaccine than the older group.
Post-market research
Since HPV vaccines became publicly available in 2006, research covering hundreds of thousands of vaccine recipients continues to confirm its safety profile as being similar to any other childhood vaccine. Research into vaccine efficacy has shown that two doses of HPV vaccine provides similar protection to those aged 14 and under as three doses provides to people aged 15 and over. As a result, many countries including New Zealand now provide HPV immunisation as a two dose regimen to those aged 9 to 14.
For more information about the vaccine see More information on HPV immunisation.