Use of hydroxychloroquine in hospitalised COVID-19 patients is associated with reduced mortality: Findings from the observational multicentre Italian CORIST study

Castelnuovo, Augusto Di; Costanzo, Simona; Antinori, Andrea; Berselli, Nausicaa; Blandi, Lorenzo; Bruno, Raffaele; Cauda, Roberto; Guaraldi, Giovanni; Menicanti, Lorenzo; My, Ilaria; Parruti, Giustino; Patti, Giuseppe; Perlini, Stefano; Santilli, Francesca; Signorelli, Carlo; Spinoni, Enrico; Stefanini, Giulio G.; Vergori, Alessandra; Ageno, Walter; Agodi, Antonella; Aiello, Luca; Agostoni, Piergiuseppe; Moghazi, Samir Al; Astuto, Marinella; Aucella, Filippo; Barbieri, Greta; Bartoloni, Alessandro; Bonaccio, Marialaura; Bonfanti, Paolo; Cacciatore, Francesco; Caiano, Lucia; Cannata, Francesco; Carrozzi, Laura; Cascio, Antonio; Ciccullo, Arturo; Cingolani, Antonella; Cipollone, Francesco; Colomba, Claudia; Crosta, Francesca; Pra, Chiara Dal; Danzi, Gian Battista; D'Ardes, Damiano; Donati, Katleen de Gaetano; Giacomo, Paola Del; Gennaro, Francesco Di; Tano, Giuseppe Di; D'Offizi, Giampiero; Filippini, Tommaso; Fusco, Francesco Maria; Gentile, Ivan; Gialluisi, Alessandro; Gini, Giancarlo; Grandone, Elvira; Grisafi, Leonardo; Guarnieri, Gabriella; Lamonica, Silvia; Landi, Francesco; Leone, Armando; Maccagni, Gloria; Maccarella, Sandro; Madaro, Andrea; Mapelli, Massimo; Maragna, Riccardo; Marra, Lorenzo; Maresca, Giulio; Marotta, Claudia; Mastroianni, Franco; Mazzitelli, Maria; Mengozzi, Alessandro; Menichetti, Francesco; Meschiari, Marianna; Minutolo, Filippo; Montineri, Arturo; Mussinelli, Roberta; Mussini, Cristina; Musso, Maria; Odone, Anna; Olivieri, Marco; Pasi, Emanuela; Petri, Francesco; Pinchera, Biagio; Pivato, Carlo A.; Poletti, Venerino; Ravaglia, Claudia; Rinaldi, Massimo; Rognoni, Andrea; Rossato, Marco; Rossi, Ilaria; Rossi, Marianna; Sabena, Anna; Salinaro, Francesco; Sangiovanni, Vincenzo; Sanrocco, Carlo; Scorzolini, Laura; Sgariglia, Raffaella; Simeone, Paola Giustina; Spinicci, Michele; Trecarichi, Enrico Maria; Venezia, Amedeo; Veronesi, Giovanni; Vettor, Roberto; Vianello, Andrea; Vinceti, Marco; Vocciante, Laura; De Caterina, Raffaele; Iacoviello, Licia

BACKGROUND: Hydroxychloroquine (HCQ) was proposed as potential treatment for COVID-19. OBJECTIVE: We set-up a multicenter Italian collaboration to investigate the relationship between HCQ therapy and COVID-19 in-hospital mortality. METHODS: In a retrospective observational study, 3,451 unselected patients hospitalized in 33 clinical centers in Italy, from February 19, 2020 to May 23, 2020, with laboratory-confirmed SARS-CoV-2 infection, were analyzed. The primary end-point in a time-to event analysis was in-hospital death, comparing patients who received HCQ with patients who did not. We used multivariable Cox proportional-hazards regression models with inverse probability for treatment weighting by propensity scores, with the addition of subgroup analyses. RESULTS: Out of 3,451 COVID-19 patients, 76.3% received HCQ. Death rates (per 1,000 person-days) for patients receiving or not HCQ were 8.9 and 15.7, respectively. After adjustment for propensity scores, we found 30% lower risk of death in patients receiving HCQ (HR=0.70; 95%CI: 0.59 to 0.84; E-value=1.67). Secondary analyses yielded similar results. The inverse association of HCQ with inpatient mortality was particularly evident in patients having elevated C-reactive protein at entry. CONCLUSIONS: HCQ use was associated with a 30% lower risk of death in COVID-19 hospitalized patients. Within the limits of an observational study and awaiting results from randomized controlled trials, these data do not discourage the use of HCQ in inpatients with COVID-19.