Should a Different Immunosuppressant Be Started to Reduce Shingles Risk?
No, switching from abatacept to methotrexate specifically to reduce shingles risk is not recommended, as methotrexate does not lower herpes zoster risk and may actually increase it compared to the general population. The most effective strategy is to administer the recombinant zoster vaccine (Shingrix) while continuing abatacept therapy.
Evidence Against Switching to Methotrexate
- Methotrexate-treated rheumatoid arthritis patients experience herpes zoster at a rate of 14.5 cases per 1,000 patient-years, compared to only 1.3 to 4.8 cases per 1,000 patient-years in the general population 1
- Herpes zoster occurrence with methotrexate appears statistically related to the drug's use, particularly in patients with longer-term rheumatic disease 1
- Methotrexate can be used as an adjunct treatment to prevent anti-TNF antibody formation in patients with a history of malignancy, but this does not indicate superior safety regarding herpes zoster 2
Comparative Risk Profile of Abatacept
- Abatacept in combination with non-methotrexate disease-modifying antirheumatic drugs demonstrates similar efficacy and tolerability to abatacept plus methotrexate, with treatment-related adverse event rates of 35.7-58.0% versus 41.7-55.9% respectively 3
- The FDA label for abatacept does not specifically highlight herpes zoster as a disproportionate risk compared to other immunosuppressants 4
Optimal Management Strategy
The recommended approach is vaccination with the recombinant zoster vaccine (Shingrix) rather than switching immunosuppressants:
- The recombinant zoster vaccine reduces herpes zoster risk by approximately 81% across immunocompromised populations 5
- Shingrix is safe for immunocompromised patients on biological therapy like abatacept, unlike the live vaccine (Zostavax) which is contraindicated 6
- The vaccine requires two doses administered 2-6 months apart and can be given at any time during abatacept therapy 6
Vaccination Timing Considerations
- Ideally, vaccination should occur before initiating immunosuppressive therapy, at least 4 weeks prior 6
- For patients already on abatacept, the recombinant vaccine can be administered without interrupting therapy 6
- Consider temporarily holding methotrexate (if used concomitantly) for 1 month before and after each vaccine dose to optimize immune response 6
Management if Herpes Zoster Develops
If shingles occurs during abatacept treatment:
- Initiate antiviral therapy promptly with acyclovir, valacyclovir, or famciclovir 7, 5
- For uncomplicated herpes zoster, oral acyclovir or valacyclovir should be continued until all lesions have scabbed 7
- Consider temporary reduction in immunosuppressive medication for disseminated or invasive herpes zoster 7
- Monitor for complete healing before resuming full-dose immunosuppression 7, 5
Common Pitfalls to Avoid
- Do not switch to methotrexate under the assumption it carries lower herpes zoster risk—the evidence demonstrates the opposite 1
- Do not administer the live zoster vaccine (Zostavax) to patients on abatacept or other biological therapy due to risk of disseminated vaccine-strain infection 6
- Do not delay vaccination waiting for "optimal timing"—for patients already on therapy, administering Shingrix promptly provides the best protection 6