<h1>Indirect comparison between immunotherapy alone and immunotherapy plus chemotherapy as first-line treatment for advanced non-small cell lung cancer: A systematic review</h1>

<h2>Creators</h2>

<ul>

  <li>Lingling Li<sup>1</sup></li>

  <li>Shu Xia<sup>2</sup></li>

  <li>Fei Xu<sup>3</sup></li>

  <li>Yu Chen<sup>4</sup></li>

  <li>Xiaoli Ren<sup>5</sup></li>

  <li>Yu Liu<sup>2</sup></li>

  <li>Yuan Chen<sup>2</sup></li>

</ul>

<h2>Description</h2>

<h3>Objectives</h3>

<p>

Use of immune checkpoint inhibitors (ICIs) as first-line treatment for advanced (stage IIIB/IV) non-small cell lung cancer (NSCLC) remains controversial. Clinical trials comparing single-drug immunotherapy (IO) with immunotherapy plus chemotherapy (IC) are lacking. We aimed to compare the efficacy of IO alone with that of IC as first-line treatment for advanced NSCLC.

</p>

<h3>Design</h3>

<p>Systematic review</p>

<h3>Data sources</h3>

<p>

PubMed, the Cochrane Library, and Embase for related studies on NSCLC; ClinicalTrials.gov, American Society of Clinical Oncology Meeting Library, and World Conference on Lung Cancer for relevant conference abstracts.

</p>

<h3>Eligibility criteria</h3>

<p>

Articles meeting the following criteria were selected:

<ul>

  <li>(1) randomized controlled trials on NSCLC treatment,</li>

  <li>(2) all individuals in the studies had not received treatment previously, and</li>

  <li>(3) research on IO monotherapy using programmed death-1/programmed death ligand-1 (PD-L1) inhibitors or IC.</li>

</ul>

</p>

<h3>Data extraction and synthesis</h3>

<p>

After reading the original literature, two reviewers independently extracted the relevant information. The primary outcomes were progression-free survival (PFS), overall survival (OS), and objective response rate (ORR). We also extracted data on treatment-related adverse events and immune-related adverse events (irAEs).

</p>

<h3>Results</h3>

<p>

Overall, 10 randomized controlled clinical trials (n = 5765) were included. As first-line treatment for advanced NSCLC, IC tended to yield better PFS, OS, and ORR than did IO. Furthermore, IC yielded significantly better PFS than IO when tumor PD-L1 expression was at least 50% (HR: 1.81, 95% CI: 1.18–2.78) and yielded a better OS and PFS when tumor PD-L1 expression was at least 1%; IO resulted in fewer adverse events than did IC. However, the incidence of irAEs was higher for IO than for IC.

</p>

<h3>Conclusions</h3>

<p>

The findings of the indirect comparison indicate that IC as first-line treatment for advanced NSCLC is significantly more effective than IO in patients with PD-L1 expression in at least 50% of tumor cells.

</p>