Efficacy and safety of Huashi Baidu granule plus Nirmatrelvir-Ritonavir combination therapy in patients with high-risk factors infected with Omicron (B.1.1.529): A multi-arm single-center, open-label, randomized controlled trial

BACKGROUND

Huashi Baidu granule (HSBD) and Paxlovid (Nirmatrelvir-Ritonavir) are antiviral Chinese patent medicine and western medicine specially developed for treating coronavirus disease 2019 (COVID-19). Their efficacy and safety in treating COVID-19 are still under investigated.

PURPOSE

To assess and compare the efficacy and safety of HSBD, Paxlovid, and the combination in treating high-risk patients infected with SARS-CoV-2 Omicron.

STUDY DESIGN

The study was a prospective single-center, open-label, randomized, controlled clinical trial conducted from April 18 to June 5, 2022. (ClinicalTrial.gov registration number: ChiCTR2200059390) METHODS: 312 severe patients aged 18 years and older infected with SARS-CoV-2 Omicron from Shuguang Hospital in Shanghai were randomly allocated to HSBD monotherapy (orally 137 g twice daily for 7 days, n = 105), Paxlovid monotherapy (orally 300 mg of Nirmatrelvir plus 100 mg of Ritonavir every 12 h for 5 days, n = 103), or combination therapy (n = 104). The primary outcome was SARS-CoV-2 nucleic acid negative conversion within 7-day treatment. The secondary outcome included hospital discharging conditions, severe conversion of symptom, and adverse events.

RESULTS

Of 312 participants, 85 (82%) of 104 in combination therapy, 71 (68%) of 105 in HSBD monotherapy, and 73 (71%) of 103 in Paxlovid monotherapy had a primary outcome event. The hazard ratios of primary outcome were 1.37 (95% CI 1.03 - 1.84, p = 0.012) for combination versus HSBD, 1.28 (0.98-1.69, p = 0.043) for combination versus Paxlovid, and 0.88 (0.66-1.18, p = 0.33) for HSBD versus Paxlovid. There was no statistical difference of efficacy between HSBD and Paxlovid, while combination therapy exhibited more effective than either alone. For secondary outcomes, the hospital discharging rates within 7 days exhibited the significant increase in combination therapy than in HSBD or Paxlovid monotherapy (71% (74/104) vs 55% (58/105) vs 52% (54/103), p < 0.05). The risk of severe conversion of symptom showed no statistical significance among three interventions (1% (1/104) vs 3% (3/105) vs 3% (3/103), p > 0.05). No severe adverse events occurred among combination therapy and monotherapies in the trial.

CONCLUSION

For patients with severe COVID-19, HSBD exhibits similar efficacy to Paxlovid, while combination therapy is more likely to increase the curative efficacy of Omicron variant than monotherapies, with few serious adverse events.

Real-World Effectiveness of Nirmatrelvir-Ritonavir and Its Acceptability in High-Risk COVID-19 Patients

BACKGROUND

Nirmatrelvir-ritonavir is highly effective in preventing severe coronavirus disease 2019 (COVID-19) in high-risk patients with mild-to-moderate severity. However, real-world performance data are limited, and the drug is not so acceptable to the COVID-19 patients at high risk who need it in Korea.

METHODS

To evaluate the effectiveness of nirmatrelvir-ritonavir, we conducted a propensity score-matched retrospective cohort study on patients with mild-to-moderate COVID-19 at high risk for a severe disease who were hospitalized at four hospitals in South Korea from February 2022 to April 2022. A total of 236 patients in the treatment group (administered nirmatrelvir-ritonavir) and 236 in the matched control group (supportive care only) were analyzed for the primary outcome, i.e., the time to oxygen support-free survival. The secondary outcome was a composite result of disease progression. The reason for not prescribing nirmatrelvir-ritonavir to the indicated patients was also investigated.

RESULTS

The treatment group showed significantly longer oxygen support-free survival than the matched control group (adjusted hazard ratio [aHR], 0.07; 95% confidence interval [CI], 0.01-0.31; P < 0.001). Multivariate Cox regression analysis showed that age (aHR, 1.03; 95% CI, 1.00-1.07), National Early Warning Score-2 at admission (aHR, 1.36; 95% CI, 1.08-1.71), nirmatrelvir-ritonavir treatment, female sex (aHR, 0.37; 95% CI, 0.15-0.88), and time from symptom onset to admission (aHR, 0.67; 95% CI, 0.48-0.95) were significantly associated with oxygen therapy. However, none of the factors were related to the composite outcome. In the unmatched control group, 19.9% of 376 patients had documented explanations for nirmatrelvir-ritonavir non-prescription, and 44.0% of these were due to contraindication criteria. In the treatment group, 10.9% of patients discontinued the medication primarily because of adverse events (71.4%), with gastrointestinal symptoms being the most common (50.0%).

CONCLUSION

Nirmatrelvir-ritonavir treatment significantly reduced oxygen therapy requirements in high-risk patients with COVID-19 during the omicron variant surge in South Korea. Physicians are encouraged to consider the active use of nirmatrelvir-ritonavir and to be watchful for gastrointestinal symptoms during medication.

Treatment Options for Patients With Mild-to-Moderate Coronavirus Disease 2019 in Korea

The coronavirus disease 2019 (COVID-19) continues to threaten public health in Korea although several surges have passed in the past 3 years since 2019. Although patients with mild-to-moderate COVID-19 can usually recover at home, antiviral therapy to prevent disease progression and hospitalization is beneficial for those at high risk of progressing to severe COVID-19. The purpose of this article was to review how antivirals have been rolled out for the treatment of COVID-19 and how domestic and international guidelines for their use have evolved. Several evidence-based treatment guidelines have been developed in Korea, including those derived from domestic studies. Although many different antiviral agents were nominated as promising therapeutics at the onset of the pandemic, most failed to show efficacy in clinical trials. Currently, three types of antiviral agents-nirmatrelvir-ritonavir, molnupiravir, and remdesivir-are available in Korea to treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Each antiviral has its advantages and disadvantages. For most individuals, nirmatrelvir/ritonavir is preferred because of its high efficacy and convenience of administration. When serious drug interactions occur or are expected with nirmatrelvir/ritonavir administration, 3 days of remdesivir treatment is shown to be a reasonable alternative. Molnupiravir may be prescribed with caution only if no other therapeutic options are available or acceptable.