Should timing be considered before abandoning convalescent plasma in covid-19? Results from the Turkish experience

INTRODUCTIONS: Results with convalescent plasma therapy in coronavirus disease 2019 (COVID-19) have been contradictory. Timing seems to be an important factor for COVID-19 convalescent plasma(CCP) to be effective. Aim of this study is to compare disease outcomes in hospitalized COVID-19 patients who were treated with CCP within first three or seven days of symptoms to patients with symptoms longer than seven days. MATERIAL AND METHODS: A multicenter retrospective study was conducted to evaluate disease outcomes in hospitalized COVID-19 patients who received CCP in addition to standard of care (SOC) approach. Patients were subgrouped according to time of CCP administration; within three days of symptoms, seven days of symptoms and after seven days of symptoms. A control group was formed from age, gender and comorbidity matched hospitalized patients who received SOC treatments without CCP. Length of hospital stay, rates of anti-inflammatory treatment initiation, intensive care unit (ICU) admission and mortality was set as outcome measures. RESULTS: A total of 223 patients were enrolled in this study, 113 patients received CCP (38 within three days, 63 within seven days, 50 after seven days of symptom onset). Rate of anti-inflammatory treatment initiation was significantly lower (38.1 % vs 62.7 %, p = 0.002, relative risk, 0.60,73; 95 % confidence interval [CI], 0.42 to 0.85) and length of hospital stay was significantly shorter (median(IQR) 8(4) days vs 9.5(5.25) days, p = 0.0025) in patients who received CCP within seven days of symptom onset when compared to SOC group. CONCLUSION: CCP therapy may provide better outcomes when applied within seven days of symptoms.