Receiving immunotherapy earlier in the day may significantly enhance survival rates for individuals diagnosed with cancer. A study published in the journal Cancer indicates that timing of anticancer treatments can play a crucial role in their effectiveness. The research highlights the impact of the body’s internal clock, or circadian rhythm, on immune responses and overall treatment outcomes.
Researchers examined the treatment patterns of 397 patients with extensive-stage small cell lung cancer at the Affiliated Cancer Hospital of Xiangya School of Medicine in China from May 2019 to October 2023. Participants received the immunotherapy drugs atezolizumab or durvalumab in combination with chemotherapy. The findings demonstrated that those who received treatment before 15:00 experienced significantly better outcomes compared to those treated later in the day.
Patients who underwent immunochemotherapy before 3:00 PM showed substantially longer progression-free survival, which measures the duration without cancer progression, as well as improved overall survival rates. After adjusting for various influencing factors, the study revealed that receiving treatment earlier in the day correlated with a remarkable 52% lower risk of cancer progression and a 63% lower risk of death.
According to senior author Yongchang Zhang, MD, from Central South University, “Adjusting infusion timing is a straightforward and easily implementable intervention that can be adopted across diverse health care settings without additional cost.” Zhang emphasized that the study’s findings possess immediate clinical applicability, suggesting that this approach has the potential to transform existing treatment protocols for small cell lung cancer.
The implications of this research extend beyond small cell lung cancer, as the role of circadian rhythms in medication efficacy could reshape treatment strategies for various diseases. Understanding how to optimize treatment timing may offer new avenues for enhancing patient care and improving survival rates in oncology.
As healthcare professionals consider the study’s findings, there is an opportunity to revisit existing treatment schedules. The potential for simple adjustments to improve patient outcomes presents a compelling case for further exploration into the timing of cancer therapies.
For more detailed insights, refer to the study titled “Overall survival according to time-of-day of immunochemotherapy for extensive-stage small cell lung cancer” published in Cancer (2025).
