What it's for (Indications)
- Human papillomavirus (HPV) type 16 and 18 vaccine (e.
- g.
- , Cervarix) is indicated for the prevention of cervical cancer, cervical intraepithelial neoplasia (CIN) grades 2 and 3, and adenocarcinoma in situ (AIS) caused by oncogenic HPV types 16 and 18.
- Additionally, it is indicated for the prevention of cervical intraepithelial neoplasia (CIN) grade 1 caused by HPV-16 and HPV-18.
- This vaccine is approved for use in females aged 9 through 25 years.
- It targets the two most prevalent high-risk HPV types responsible for the majority of cervical cancers globally.
- Vaccination does not eliminate the need for routine cervical cancer screening, as it does not protect against all HPV types that can cause cervical cancer.
Dosage Information
| Type | Guideline |
|---|---|
| Standard | The HPV type 16 and 18 vaccine (e.g., Cervarix) is administered intramuscularly as a series of injections. The recommended dosage schedule varies by age. For individuals aged 9 to 14 years, a 2-dose schedule is typically employed: the first dose followed by a second dose 6 months later. For individuals aged 15 to 25 years, a 3-dose schedule is recommended: the first dose, followed by a second dose 1 month later, and a third dose 6 months after the first dose. It is crucial to adhere to the recommended dosing schedule to achieve optimal immune response and protection. No data exist on the interchangeability of HPV vaccines from different manufacturers. |
Safety & Warnings
Common Side Effects
- Common adverse reactions reported with HPV type 16 and 18 vaccine (e.
- g.
- , Cervarix) are predominantly mild to moderate and typically resolve without intervention.
- These include injection site reactions such as pain, redness (erythema), and swelling (induration).
- Systemic reactions commonly reported are headache, fatigue, myalgia (muscle pain), arthralgia (joint pain), and gastrointestinal symptoms like nausea, vomiting, diarrhea, and abdominal pain.
- Less common but more serious adverse events can include syncope (fainting), which may be accompanied by tonic-clonic movements and should prompt appropriate observation post-vaccination.
- Hypersensitivity reactions, including anaphylaxis, although rare, are possible and require immediate medical attention.
Serious Warnings
- Black Box Warning: While HPV type 16 and 18 vaccines (e.g., Cervarix) do not carry an FDA-mandated Black Box Warning, clinicians should be aware of 'Serious Warnings' pertaining to vaccination. One primary concern is syncope, or fainting, which can occur after vaccination, particularly among adolescents and young adults. This neurocardiogenic response often manifests with pallor, sweating, and may be accompanied by tonic-clonic movements, emphasizing the importance of observation for at least 15 minutes post-vaccination to prevent injury from falls. Furthermore, individuals with a known history of severe allergic reactions (e.g., anaphylaxis) to any vaccine component or a prior dose are absolutely contraindicated. Though rare, severe hypersensitivity reactions can occur, necessitating immediate access to resuscitative measures. Healthcare providers should also counsel patients that the vaccine does not treat active HPV infections or replace routine cervical cancer screening.
- While there is no specific FDA Black Box Warning for HPV type 16 and 18 vaccines, several serious warnings and precautions warrant consideration.
- Syncope (fainting) can occur after vaccination, particularly in adolescents and young adults.
- Patients should be observed for approximately 15 minutes after administration to mitigate risks associated with falls and injuries.
- Patients with a history of severe allergic reactions (e.
- g.
- , anaphylaxis) to any component of the vaccine or following a previous dose are strictly contraindicated.
- Vaccination should be deferred in individuals experiencing an acute severe febrile illness; however, minor afebrile illnesses are not typically a contraindication.
- The vaccine may not provide full protection in all recipients and does not treat existing HPV infections or HPV-related diseases.
- It also does not substitute for routine cervical cancer screening.
How it Works (Mechanism of Action)
The Human Papillomavirus type 16 and 18 vaccine (e.g., Cervarix) is a recombinant bivalent vaccine composed of highly purified, non-infectious virus-like particles (VLPs) derived from the L1 capsid protein of HPV types 16 and 18. These VLPs are produced by recombinant DNA technology using a baculovirus expression system and lack viral DNA, thus rendering them incapable of causing infection or disease. When administered, these VLPs elicit a robust humoral immune response, stimulating the production of high titers of type-specific neutralizing antibodies against HPV-16 and HPV-18. The vaccine also contains an adjuvant system (AS04), which significantly enhances the magnitude and duration of the immune response by promoting antigen presentation and lymphocyte activation, providing durable protection against subsequent exposure to these oncogenic HPV types.
Commercial Brands (Alternatives)
No other brands found for this formula.