Vaccination Before Immune-Modifying Therapy
A staged clinical reasoning case
Before you begin
This fictional composite case progresses through eight clinical decisions. Choose a response before the reasoning appears. The activity is unscored and takes approximately 15–20 minutes.
Later findings remain hidden until you complete the current stage.
Case debrief
The case required more than identifying vaccines on an age-based schedule. The final plan depended on documented immunity, occupational risk, the distinction between live and nonlive vaccines, the timing and mechanism of immune-modifying therapy, and a laboratory finding that required prevention beyond vaccination.
| Decision point | Finding | Reasoning problem | Implication |
|---|---|---|---|
| Evidence of immunity | One documented MMR dose; clinician-verified varicella history | Different antigens require different evidence standards | Complete MMR protection without giving unnecessary varicella vaccine |
| Vaccine type | MMR is live; influenza, PCV20, and RZV are nonlive | Safety and immunogenicity are separate questions | Vaccinate before B-cell depletion and preserve required timing |
| HBV serology | HBsAg negative, anti-HBc positive, anti-HBs positive | Resolved infection still carries reactivation risk with anti-CD20 therapy | Vaccination cannot replace specialist-guided antiviral prevention and monitoring |
| Communication | Concern about receiving several vaccines together | Reactogenicity, protection, convenience, and treatment timing must be separated | Give a clear recommendation, address the specific concern, and preserve follow-through |
Clinical reasoning priorities
- Use the current schedule, but interpret it through documented history, occupation, pregnancy status, immune competence, and planned therapy.
- Patient recollection, birth year, serology, and prior disease are not interchangeable; each vaccine has specific evidence-of-immunity criteria.
- Nonlive vaccines are generally safe during immunosuppression, but response may be reduced. Timing can affect effectiveness even when safety is not the concern.
- Live vaccines require medication-specific assessment and adequate separation from substantial immunosuppression.
- Recombinant zoster vaccine prevents shingles; it does not substitute for primary varicella vaccination in a susceptible person.
- An interrupted multidose series is continued rather than restarted.
- HBV screening before anti-CD20 therapy is an infection-prevention decision, but a positive core antibody is not corrected by giving more hepatitis B vaccine.
Clinical boundaries
This case uses a rheumatology-specific medication plan to illustrate general vaccine principles. Decisions about holding therapy, delaying treatment, or vaccinating between anti-CD20 cycles must be individualized with the prescribing specialist because the risk of disease flare may outweigh an incremental improvement in vaccine response. Current product guidance and specialty recommendations should be checked at the point of care (Bass et al., 2023; Centers for Disease Control and Prevention [CDC], 2024a).
References
Bass, A. R., Chakravarty, E., Akl, E. A., Bingham, C. O., Calabrese, L., Cappelli, L. C., Johnson, S. R., Imundo, L. F., Winthrop, K. L., Arasaratnam, R. J., Baden, L. R., Berard, R., Bridges, S. L., Jr., Cheah, J. T. L., Curtis, J. R., Ferguson, P. J., Hakkarinen, I., Onel, K. B., Schultz, G., . . . Reston, J. (2023). 2022 American College of Rheumatology guideline for vaccinations in patients with rheumatic and musculoskeletal diseases. Arthritis Care & Research, 75(3), 449–464. https://doi.org/10.1002/acr.25045
Centers for Disease Control and Prevention. (2024a, June 26). Altered immunocompetence. https://www.cdc.gov/vaccines/hcp/imz-best-practices/altered-immunocompetence.html
Centers for Disease Control and Prevention. (2024b, July 9). Clinical considerations for Shingrix use in immunocompromised adults aged ≥19 years. https://www.cdc.gov/shingles/hcp/vaccine-considerations/immunocompromised-adults.html
Centers for Disease Control and Prevention. (2025, July 2). Adult immunization schedule notes. https://www.cdc.gov/vaccines/hcp/imz-schedules/adult-notes.html
U.S. Food and Drug Administration. (2025). Riabi (rituximab-arrx) injection: Prescribing information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2025/761140s004lbl.pdf