UMEM Educational Pearls

Patient

·         A North America multicenter study involving 821 asymptomatic patients who had exposure to Covid-19-positive patients.  The study was double-blind, placebo-controlled randomized trial.

Intervention

·         Within 4 days of exposure, participants were randomized to receive hydroxychloroquine.  Dose of hydroxychloroquine was 800 mg once then 600 mg in 6-8 hours then 600 mg daily for 4 more days.

·         There were 414 patients in this arm. Median age 41 years [IQR 33-51]

Comparison:

·         Placebo treatment.  There were 407 patients in this arm. Median age 40years [IQR 32-50]

Outcome:

·         Incidence of either laboratory-confirmed Covid-19 or Covid-19 symptoms within 14 days.

Results:

·         49 (11.8%) patients with treatment had Covid-19 findings (positive tests or symptoms)

·         58 (14.3%) patients with placebo had Covid-19 findings (p=0.35). 

·         The absolute difference was -2.4%.  The number need to treat (NNT) to prevent one infection is 42 patients.  Number needed to harm is 50 patients.

·         Symptoms were fatigue (49.5%), cough (44.9%), sore throat (40.2%) myalgia (37.4%), fever (34.6%), anosmia (23.4%), shortness of breath (18.7%).

 

Conclusion:

Hydroxychloroquine prophylaxis did not prevent post-exposure Covid-19 infection.

References

A Randomized Trial of Hydroxychloroquine as Postexposure Prophylaxis for Covid-19.

Boulware DR, Pullen MF, Bangdiwala AS, Pastick KA, Lofgren SM, Okafor EC, Skipper CP, Nascene AA, Nicol MR, Abassi M, Engen NW, Cheng MP, LaBar D, Lother SA, MacKenzie LJ, Drobot G, Marten N, Zarychanski R, Kelly LE, Schwartz IS, McDonald EG, Rajasingham R, Lee TC, Hullsiek KH.

N Engl J Med. 2020 Jun 3. doi: 10.1056/NEJMoa2016638. Online ahead of print.

PMID: 32492293