COVID-19 pneumonia is associated with possible hospitalization. In the current study, most (53.9%) of the hospitalized patients with COVID-19 pneumonia were men—similar to that in a previous study [22]. Remdesivir was used to treat nearly one-fourth of all current patients with COVID-19 pneumonia; this is in contrast to a similar previous study that administered remdesivir more frequently [23]. This difference may be due to various reasons, clarifying which was beyond the scope of the present study.
A study found that older age and a large number of comorbidities were both associated with higher severity and mortality in patients with COVID-19: 2.4 times more men than women died of COVID-19 (70.3 vs. 29.7%) [24]. These results corroborate the current findings. Older age and underlying medical conditions may thus be associated with an increased risk of persistent COVID-19 pneumonia symptoms.
Large-scale cohort studies on remdesivir-treated patients with COVID-19 have reported improved clinical outcomes; however, the relevant data available regarding older patients remain limited. Nevertheless, a retrospective study assessed the potential benefit of remdesivir in ≥ 80-year-old patients hospitalized with COVID-19 who were unvaccinated [25]. In these patients, remdesivir use remained associated with a lower 30-day all-cause mortality rate after adjustments for age, sex, and low mortality–related variables. In contrast, the remdesivir recipients in this study were, on average, 10 years younger than those in the aforementioned study. Moreover, in the current study, the remdesivir recipients were approximately 10 years older than the nonrecipients.
In another selective retrospective cohort study using health insurance claims and billing data, remdesivir treatment was associated with significantly decreased overall inpatient mortality in patients hospitalized with COVID-19 [26]. These results, obtained using data collected during routine clinical practice and state-of-the-art methods, corroborated the results of randomized clinical trials [27, 8]. These results also supported the results of Beigel et al. [8], who found low in-hospital mortality in the remdesivir-treated group; however, this result was nonsignificant because the study of Beigel et al. was not designed for this secondary endpoint.
In the World Health Organization Solidarity Study, similar in-hospital mortality outcomes were noted in adults hospitalized with COVID-19 pneumonia who were treated with remdesivir and those who were treated with the local standard of care; moreover, a significant (13%) reduction was noted in the mortality rate of the patients who required oxygen but not mechanical ventilation [28, 26]. These results were corroborated by randomized controlled trial results, which demonstrated that outpatient use of remdesivir leads to an 87% reduction in the hospitalization risk of high-risk patients with COVID-19 [29, 26].
A retrospective study compared data from an international, randomized, open-label Phase 3 study on remdesivir in patients with severe COVID-19 with data from an international, contemporary clinical cohort study on patients receiving standard of care [30, 26]. The authors noted that mortality within 28 days of follow-up was lower in remdesivir recipients than in standard-of-care recipients [30, 26]. Next, mortality was compared between evaluated COVID-19 patients who received remdesivir and those who received supportive care alone [31, 26]. The results demonstrated an association between remdesivir treatment and low mortality in patients who received low-flow oxygen [31, 26]. However, another study observed no association between mortality and remdesivir in patients with COVID-19 pneumonia [31, 26].
In the current study, approximately 74% of the remdesivir recipients survived, indicating the effectiveness of remdesivir. Moreover, the mortality risk did not demonstrate significant differences between older and younger patients with COVID-19 pneumonia. Furthermore, no significant sex differences were noted among deceased and surviving remdesivir recipients and nonrecipients. Nevertheless, considerable age differences were noted among the four patient groups. Finally, many COVID-19 pneumonia patients died regardless of whether they received remdesivir.
The World Health Organization Solidarity Study reported that remdesivir treatment neither shortened the length of hospital stay nor improved survival in patients with COVID-19 pneumonia [28]. However, other studies have reported a reduction in the length of hospital stay in remdesivir-treated patients with COVID-19 pneumonia [32].
A retrospective study examined 76 COVID-19 pneumonia patients who received remdesivir [33]; however, in the current study, half as many patients with COVID-19 pneumonia received remdesivir. Moreover, the study population in the previous study included 47.4% men and 52.6% women [33]; this sex distribution was similar to that in the current study. Furthermore, in a previous study [33], most patients had at least one comorbidity, with hypertension being the most common; this result was similar to that of the current study. The median length of hospital stay for remdesivir recipients was 10.1 days in the previous study [33], whereas it was 11.9 days in the current study. In a previous study [33], 14 (18.4%) patients with COVID-19 pneumonia (including 5 [13.9%] men and 9 [22.5%] women) died; in the current study, this number was 10 (26.3%; including 4 [40%] men and 6 [60%] women). However, mortality demonstrated no significant sex differences in the previous and current studies [33]. Therefore, remdesivir may have clinical efficacy in the treatment of severe COVID-19 pneumonia within a community. Although both the previous and current studies were small-scale studies, their results provide a reference for remdesivir use in other hospitals.
A study reported that the effectiveness of remdesivir was 78% in patients with COVID-19 pneumonia [13], which is similar to the effectiveness observed here (73.7%). These results indicate the importance of initiating remdesivir treatment in patients with COVID-19 pneumonia as early as possible.
Limitations
This study has some limitations. First, testing and rapid aggressive treatment are key to effective COVID-19 pneumonia management. This was a single-center study; therefore, our results may not be generalizable. Patients are recommended for COVID-19 testing at the discretion of their health care providers, and testing practices and skills may vary widely among health care providers and testing facilities. This may lead to COVID-19 pneumonia cases being underreported. Finally, only a few of the included patients with COVID-19 pneumonia received remdesivir; the potential reasons for this observation were not examined in this study. Moreover, most of the included patients were elderly.