A Randomized, Double-Blind, Placebo-Controlled Phase IIa Study of Hydroxychloroquine, Vitamin C, Vitamin D, and Zinc for the Prevention of COVID-19 Infection

Hazan et al., NCT04335084, HELPCOVID-19, NCT04335084, Nov 2026
Pre-exposure prophylaxisRCT · NCT04335084 · 254 patients · USA
HCQ for COVID-19
HELPCOVID-19 Hazan et al. NCT04335084 · November 2026
Outcome
Improvement
Relative Risk · 95% CI
Case
47%0.53 · 0.22–1.28
00.511.52+
← HCQ reduces riskIncreased risk →
Fewer cases with HCQ
Not statistically significant · p = 0.22

HCQ for COVID-19

1st treatment shown to reduce risk in March 2020, now with p < 0.0000000001 from 426 studies, used in 59 countries.
Lower risk for mortality, hospitalization, progression, recovery, cases, and viral clearance.

No treatment is 100% effective.
Protocols combine treatments.

6,700+ studies · 220+ treatments

c19early.org
Meta-analysis
RCT 172 medical workers in the USA shower lower COVID-19 cases with HCQ prophylaxis without statistical significance. All patients received vitamin C, vitamin D, and zinc.
Standard of Care (SOC) for COVID-19 in the study country, the USA, is very poor with very low average efficacy for approved treatments1. Only expensive, high-profit treatments were approved for early treatment. Low-cost treatments were excluded, reducing the probability of early treatment due to access and cost barriers, and eliminating complementary and synergistic benefits seen with many low-cost treatments.
Important missing comments or errors? Let us know.
risk of case, 46.9% lower, RR 0.53, p = 0.22, treatment 7 of 90 (7.8%), control 12 of 82 (14.6%), NNT 15.
Effect extraction follows pre-specified rules prioritizing more serious outcomes. Submit updates
Hazan et al., 4 Nov 2026, Double Blind Randomized Controlled Trial, placebo-controlled, USA, preprint, 1 author, trial NCT04335084 (history) (HELPCOVID-19). Contact: drhazan@progenabiome.com.
$0 $500 $1,000+ Efficacy vs. cost for COVID-19 treatment protocols c19early.org November 2026 USA Angola Colombia Kenya Mozambique Myanmar South Africa Peru Philippines Vietnam Japan Argentina Nepal Iran Bangladesh Ethiopia Ghana Germany Mexico South Korea United Kingdom Saudi Arabia Algeria Morocco Yemen Poland Uzbekistan India China Venezuela DR Congo Madagascar Thailand Uganda Egypt Nigeria Taiwan Fiji Zambia Bosnia-Herzegovina Jordan Georgia Switzerland Dominican Republic Bolivia Côte d'Ivoire Eritrea Togo Bulgaria Greece Slovakia Iceland New Zealand Trinidad and Tobago Mongolia Czechia Belarus Israel Haiti North Macedonia Hong Kong Qatar Panama Serbia USA favored high-profit treatments.The average efficacy of treatments was very low.High-cost protocols reduce early treatment, andforgo complementary/synergistic benefits. More effective More expensive 75% 50% 25% ≤0%
$0 $500 $1,000+ Efficacy vs. cost for COVID-19treatment protocols worldwide c19early.org November 2026 USA Angola Colombia Kenya Mozambique Myanmar South Africa Peru Philippines Vietnam Japan Argentina Nepal Iran Bangladesh Ethiopia Ghana Germany Mexico South Korea United Kingdom Saudi Arabia Algeria Morocco Yemen Poland Uzbekistan India China Venezuela DR Congo Madagascar Thailand Uganda Egypt Taiwan Fiji Zambia Jordan Georgia Switzerland Dominican Rep. Bolivia Côte d'Ivoire Eritrea Togo Sri Lanka Bulgaria Greece Slovakia New Zealand Trinidad and Tobago Mongolia Czechia Belarus Israel North Macedonia Hong Kong Qatar Panama Serbia USA favored high-profit treatments.The average efficacy was very low.High-cost protocols reduce early treatment,and forgo complementary/synergistic benefits. More effective More expensive 75% 50% 25% ≤0%
Please send us corrections, updates, or comments. c19early involves the extraction of 200,000+ datapoints from thousands of papers. Community updates help ensure high accuracy. Treatments and other interventions are complementary. All practical, effective, and safe means should be used based on risk/benefit analysis. No treatment or intervention is 100% available and effective for all current and future variants. We do not provide medical advice. Before taking any medication, consult a qualified physician who can provide personalized advice and details of risks and benefits based on your medical history and situation. IMA and WCH provide treatment protocols.
  or use drag and drop   
Submit    
Post
Share
@CovidAnalysis
FAQ
Public domain CC0 1.0