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Causality: well established
Causality assessment · Causality: well established
Zidovudine and Anaemia / bone-marrow suppression: is the FAERS signal real?
A written Bradford Hill assessment of one drug–event pair. The grade is a judgement about the signal, not a statement that this drug causes this event in any one person; FAERS counts are reports, not rates.
Zidovudine ↔ Anaemia / bone-marrow suppression
n=935 co-reports · PRR 7.8 · ROR 8.3
Zidovudine, an early HIV drug, suppresses the bone marrow and causes anaemia, usually a macrocytic anaemia that appears after weeks to months of therapy, especially at higher doses. It is a direct, dose-related consequence of the drug's inhibition of DNA synthesis in marrow cells rather than an idiosyncratic reaction, and it is why blood counts are monitored during treatment. The 935 co-reports (PRR 7.8) reflect both the real effect and zidovudine's role in HIV care.
Regulatory basis: zidovudine prescribing information (haematologic toxicity warning; blood-count monitoring). Established zidovudine-myelosuppression literature.
| Bradford Hill viewpoint | Status | Note |
|---|---|---|
| Temporality (necessary) | met | Anaemia develops during therapy and improves after dose reduction or withdrawal |
| Strength | met | PRR 8 on a large co-report count |
| Consistency | met | Reproduced across HIV trials |
| Specificity | met | A recognised zidovudine effect, less typical of newer antivirals |
| Biological gradient | met | Dose-related |
| Plausibility | met | Marrow-cell DNA-synthesis inhibition is the mechanism |
| Coherence | met | Coheres with the labelled blood-count monitoring |
| Experiment | partial | Dechallenge (dose reduction/withdrawal) allows marrow recovery; no randomized trial |
| Analogy | met | Analogous to myelosuppression from ganciclovir and other nucleoside analogues |
This page's own qualitative read, not an automated/citation-gated assessment.
✗ No ClinicalTrials.gov results-posting trial in the top search hits for zidovudine captured anaemia as a coded event; marrow suppression is captured through routine blood-count monitoring rather than coded trial endpoints.