Is it safe to discontinue primary Pneumocystis jiroveci pneumonia prophylaxis in patients with virologically suppressed HIV infection and a CD4 cell count <200 cells/microL?

BACKGROUND: Current guidelines suggest that primary prophylaxis for Pneumocystis jiroveci pneumonia (PcP) can be safely stopped in human immunodeficiency virus (HIV)-infected patients who are receiving combined antiretroviral therapy (cART) and who have a CD4 cell count >200 cells/microL. There are few data regarding the incidence of PcP or safety of stopping prophylaxis in virologically suppressed patients with CD4 cell counts of 101-200 cells/microL.
METHODS: The Opportunistic Infections Project Team of the Collaboration of Observational HIV Epidemiological Research in Europe (COHERE) included data from 23,412 patients from 12 European cohorts who started taking cART after 1997. Poisson regression was used to model incidence rate ratios (IRRs) of primary PcP.
RESULTS: There were 253 PcP cases during 107,016 person-years of follow-up (PYFU). Prophylaxis significantly reduced the incidence of PcP among patients with current CD4 cell counts 100 cells/microL (adjusted IRR, 0.41; 95% confidence interval [CI], 0.27-0.60) but not significantly among those with current CD4 cell counts of 101-200 cells/microL (adjusted IRR, 0.63; 95% CI, 0.34-1.17). The incidence of PcP among patients who had a current CD4 cell count of 100-200 cells/microL, who had a viral load <400 copies/mL, and who were receiving prophylaxis was 2.1 cases per 1000 PYFU (95% CI, 0.8-4.3 cases per 1000 PYFU; 7 events occurred during 3363 PYFU), whereas 1.2 cases per 1000 PYFU (95% CI, 0.2-4.5 cases per 1000 PYFU; 2 events occurred during 1614 PYFU) occurred among persons who were not receiving prophylaxis (adjusted IRR, 1.65; 95% CI, 0.33-8.15). Among patients who discontinued PcP prophylaxis after starting cART, the incidence of primary PcP was 0 cases per 1000 PYFU (95% CI, 0.0-2.7 cases per 1000 PYFU; 0 events occurred during 1363 PYFU) for patients who had a current CD4 cell count of 101-200 cells/microL and who were receiving cART.
CONCLUSIONS: The incidence of primary PcP among patients who had virologically suppressed HIV infection, were receiving cART, and who had CD4 cell counts >100 cells/microL was low irrespective of prophylaxis use. Discontinuation of prophylaxis may be safe in patients with CD4 counts of 101-200 cells/microL and suppressed viral load.