Lung cancer changes everything. One diagnosis can shift how you see every breath, every cough, every doctor’s visit. For many, treatment brings hope — but also fear of harsh side effects that can feel almost as hard as the disease itself.
Advanced non-small cell lung cancer (NSCLC) affects hundreds of thousands worldwide. It’s the most common type of lung cancer. Many patients now get PD-1 inhibitors — drugs that help the immune system fight cancer. Pembrolizumab has long been a go-to choice. But newer options like sintilimab, tislelizumab, and camrelizumab are being used more, even though we haven’t had clear proof they work the same or are as safe.
Until now.
Doctors wanted to know: do these newer drugs measure up? Most past studies were tightly controlled trials. But real life is messier. Patients have different health histories. They get different combinations of treatments. So a new study looked at how these drugs performed outside the lab — in real clinics, with real patients.
Not all immune drugs act the same
The study reviewed records from over 400 patients treated between 2019 and 2022. All had stage IIIB or IV NSCLC. They received one of four PD-1 inhibitors: pembrolizumab, sintilimab, tislelizumab, or camrelizumab — either alone or with chemo. Researchers then tracked how long patients lived without their cancer worsening and how often they had serious side effects.
Here’s what changed
For squamous NSCLC — one major subtype — all four drugs worked about the same. No clear winner. But for nonsquamous NSCLC, a different story emerged. Patients who got camrelizumab after prior treatment had faster disease progression and shorter survival compared to those on pembrolizumab. That’s a red flag — though the number of patients on camrelizumab was small, so it’s not final proof.
The real surprise came with safety
Sintilimab stood out. It caused significantly fewer immune-related side effects — things like rash, thyroid problems, or liver inflammation — than the other three drugs. This was true for all levels of severity, including the most serious (grade 3–5). And it did this while matching pembrolizumab in shrinking tumors.
Think of your immune system like a security team inside your body. Cancer can sneak past by wearing a disguise — a “do not attack” signal. PD-1 inhibitors remove that signal, like disarming an invisibility cloak. But sometimes, the security team gets overexcited and attacks healthy tissue. That’s what causes immune-related side effects. Sintilimab may be better at targeting only cancer — like a smarter alarm system that rarely goes off by mistake.
This doesn't mean this treatment is available yet.
The study looked back at medical records, so it’s not a randomized trial. That means other factors — like patient age, other illnesses, or treatment timing — could have influenced results. Still, the safety edge for sintilimab was strong and consistent. Experts say this adds valuable real-world evidence, especially for doctors weighing which drug to choose.
What this means for patients
If you or a loved one is facing advanced lung cancer, this study offers new insight. Sintilimab may offer a safer path — especially if avoiding serious side effects is a top concern. But it’s not approved everywhere, and access varies by country. Talk to your oncologist about what’s best for your specific case.
Here’s the catch
Camrelizumab’s poorer results were only seen in later treatments for nonsquamous cancer. The group was small — just 35 patients total. So this finding raises questions but doesn’t prove camrelizumab is worse. More research is needed.
The road ahead
Next, researchers need head-to-head trials — where patients are randomly assigned to different drugs. That would give clearer answers. Until then, this real-world data helps fill the gap. It reminds us that not all PD-1 inhibitors are the same — even if they work the same way in theory.
One day, treatment choices may depend not just on how well a drug fights cancer, but on how gently it treats the person taking it. That future is getting closer.
Note: This article is based on a real-world retrospective study published in Frontiers in Medicine on April 28, 2026. It is not medical advice. Always consult your healthcare provider about treatment options.