About IXCHIQ®

About IXCHIQ® powder and solvent for solution for injection. Chikungunya vaccine (live)

IXCHIQ® is a live, attenuated vaccine indicated for active immunisation for the prevention of disease caused by the chikungunya virus in individuals aged 18 years and older. It is administered as a single 0.5 mL intramuscular injection (in the deltoid muscle) after reconstitution. The vaccine should be stored in a refrigerator (2°C to 8°C) in its original packaging and must be used within two hours of reconstitution.¹

IXCHIQ® clinical data

IXCHIQ® Phase III trials

Please note, no efficacy data are available for IXCHIQ^®. The clinical efficacy was inferred from a post-vaccination CHIKV-specific neutralising antibody titre threshold, which is considered reasonably likely to predict protection against CHIKV.¹

IXCHIQ^® has been studied in two Phase III clinical trials:

6-month trial

This was a multicentre, randomised, placebo-controlled, double-blinded pivotal study evaluating the safety and immunogenicity of IXCHIQ® in 4128 participants (362 participants made up the per-protocol population). A single dose induced a seroresponse in 98.9% of participants after 28 days, which was the primary endpoint. Seroresponse is defined as a CHIKV neutralising antibody titre ≥150 by μPRNT50 for baseline negative participants 28 days post-vaccination.²

28 days and six months post-vaccination (participants 18 years and older)^1,2

*Defined as CHIKV neutralising antibody titre ≥150 by μPRNT50 (50% plaque reduction in a micro plaque reduction neutralisation test) for baseline negative participants 28 days after first vaccination. The lower bound of the 95% CI for the SRR at Day 29 in IXCHIQ® group needed to exceed 70% neutralising antibody titres determined using μPRNT50 assay.²

2-year trial

A single-arm Phase IIIb study assessed longer-term immunogenicity and safety. IXCHIQ® demonstrated seroresponse up to 24 months post-vaccination. Seroresponse was similar in older adults (≥65 years, 98% seroresponse rate) and younger adults (18–64 years, 96.6% seroresponse rate) at 24 months.³

12 months and 24 months post-vaccination (participants 18 years and older)³

*Defined as CHIKV neutralising antibody titre ≥150 by μPRNT50 (50% plaque reduction in a micro plaque reduction neutralisation test) for baseline negative participants 28 days after first vaccination. The lower bound of the 95% CI for the SRR at Day 29 in IXCHIQ® group needed to exceed 70% neutralising antibody titres determined using μPRNT50 assay.¹

Adverse reactions

MHRA drug safety update

The Commission on Human Medicines (CHM) has temporarily restricted the use of IXCHIQ® in people aged 65 and over until a further safety review has been concluded. This precautionary measure is based on global data highlighting 23 cases of serious adverse reactions, including two fatal outcomes, in individuals aged 62–89 who received the vaccine. There are currently no changes in recommendations for individuals aged 18–64 years.⁴

In the clinical trials, most IXCHIQ® adverse reactions were mild to moderate and typically resolved within 2–3 days.²

• The most common vaccination site reactions were tenderness (10.8%) and pain (6.1%).¹

• The most common systemic adverse reactions observed were: headache (32%), fatigue (29.4%), myalgia (23.7%), arthralgia (16.6%), fever (13.8%), and nausea (11.4%).¹

Please refer to the summary of product characteristics for more information on contraindications, special warnings and precautions for use, interaction with other medicinal products, and fertility, pregnancy and lactation.

When should prevention with IXCHIQ® be considered?^5-7

You should consider prevention with IXCHIQ® for:

• Frequent travellers to chikungunya risk area
• Travellers to chikungunya outbreak areas
• People moving to chikungunya-endemic countries
• Long-term travellers to chikungunya risk areas
• Spontaneous travellers with unplanned itineraries
• Short-term travellers with increased risk based on planned activity and time of travel