Efficacy And Safety Of Durvalumab + Chemotherapy Vs. Atezolizumab + Chemotherapy In The Treatment Of Small-cell Lung Cancer

Objective: Programmed cell death-ligand 1 inhibitor(PD-L1 inhibitor)plus chemotherapy has made significant progress in the treatment of small-cell lung cancer(SCLC).Among them,atezolizumab and durvalumab have been granted first-line indications for SCLC in China.However,in real-world clinical practice,these two drugs are not exclusively used in first-line but also in second-line or later clinical applications.Furthermore,there is limited data about the difference of efficacy and safety in Chinese population.This study sought to assess the efficacy and safety of these 2 PD-L1 inhibitors plus chemotherapy in the treatment of SCLC in a multicenter real-world setting.Methods: We conducted this retrospective,multicenter,real-world study to assess the efficacy and safety of 2 anti-PD-L1 inhibitors(i.e.,atezolizumab or durvalumab)plus chemotherapy in the treatment of SCLC.To collect and analyze clinical data from patients admitted to the Anhui Provincial Hospital,the Affiliated Hospital of Anhui Medical University and the Anhui Chest Hospital from February 1,2020 to April 30,2022.Both progression-free survival(PFS)and overall survival(OS)were evaluated according to the Response Evaluation Criteria in Solid Tumors(version 1.1).The safety of the treatments was evaluated for all patients who received at least 1 dose of the designated study treatment.Results: 1.A total of 143 patients were enrolled in this study.Among these patients,100 received durvalumab,and the rest received atezolizumab.The clinical baseline characteristics of the two groups were basically balanced before using PD-L1 inhibitors.2.The median OS time of the patients who received durvalumab or atezolizumab as the first-line treatment were 22.0 and 10.0 months,respectively [hazard ratio(HR)=0.49,95%confidence interval(CI): 0.27–0.90;P=0.03].3.In terms of survival analysis of patients with brain metastasis(BM),the median PFS time of the patients without BM treated with durvalumab plus chemotherapy(5.5 months) was longer than that of those with BM(4.0 months),and the difference was statically significant(P=0.03).However,in the treatment scheme of atezolizumab plus chemotherapy,there was no effect of brain metastasis on survival.4.The addition of radiotherapy(including chest radiotherapy,prophylactic cranial irradiation and bone radiotherapy)to treatment with PD-L1 inhibitors in combination with chemotherapy has a tendency to improve long-term survival.5.The incidence of immune-related adverse events(IRAEs)during PD-L1 inhibitor treatment was not significantly different between the two groups(P>0.05)and had a manageable safety profile,with no patient dying as a result of an IRAE.6.During treatment with PD-L1 inhibitors in combination with chemotherapy,radiotherapy was not associated with the development of IRAE(P=0.42),but increased the risk of immune-related pneumonitis(P=0.026).Conclusion: In this multicentre real-world study,the efficacy and safety analysis of PDL1 inhibitors(dulvalizumab or atelelizumab)in combination with chemotherapy in patients with SCLC was compared.This study showed that first-line durvalumab in combination with chemotherapy was more beneficial in terms of long-term survival and that there was no significant difference in the incidence of IRAEs between durvalumab and atezolizumab during its use.In addition,appropriate radiotherapy during treatment with immune checkpoint inhibitors in combination with chemotherapy may prolong survival,but the occurrence of immune-related pneumonitis should be vigilant.