0
0
A growing body of research suggests that the timing of immunotherapy infusions could have a significant impact on patient survival outcomes across various types of cancer. A recent meta-analysis, which examined data from over a dozen studies, found that immunotherapy administered earlier in the day substantially improves progression-free and overall survival for several cancers, including metastatic melanoma, renal cell carcinoma, esophageal cancer, and non–small cell lung cancer (NSCLC).
The Evidence Behind Timing
A 2023 study on stage IV melanoma revealed a striking difference in survival rates based on the time of day patients received their immunotherapy infusions. Patients who received more than 75% of their infusions after 2 PM had a median overall survival of 14.9 months, compared to 38.1 months for those who received earlier infusions.
Similarly, a study on older patients with locally advanced NSCLC found that those who received at least half of their durvalumab infusions within three hours of sunset had more than twice the risk for distant metastases and worse progression-free survival.
“Cancer type after cancer type, when you try this with immunotherapy, it replicates,” said Dr. David Qian, a thoracic radiation oncologist at MD Anderson Cancer Center and an author of the meta-analysis. “I think there’s real underlying science going on.”
The Science of Chronotherapy
The concept of chronotherapy—administering treatments based on the body’s circadian rhythms—is gaining attention in oncology. Research indicates that lymphocyte levels in tumors peak earlier in the day and decline as the day progresses. Because immunotherapy relies on lymphocytes to be effective, administering it during peak immune activity may enhance its effectiveness.
Additionally, studies on metastatic renal cell carcinoma found that T-cell activity in response to immunotherapy was highest earlier in the day, aligning with improved survival rates.
Does Timing Matter for Other Cancer Treatments?
While immunotherapy appears to be more effective earlier in the day, the same does not necessarily apply to other cancer treatments. Some studies suggest that radiotherapy may be more beneficial later in the day, while chemotherapy findings remain inconsistent. A recent study on prostate cancer radiotherapy found no significant difference in outcomes based on treatment timing, although race-specific benefits were observed.
“On the whole, available data do not support the claim that chrono-chemotherapy is broadly beneficial for the treatment of any form of cancer, and it is not commonly practiced,” noted Dr. Aziz Sancar and Dr. Russell N. Van Gelder in a recent review published in Science.
Challenges in Implementing Time-Based Treatment
Despite compelling evidence, time-based immunotherapy has not yet been widely adopted in clinical practice. Logistical constraints, such as infusion preparation times and pharmacy schedules, often dictate when patients receive treatment.
Additionally, a lack of large, multicenter randomized trials has prevented widespread acceptance. Efforts to secure funding for such trials have been met with skepticism, as drug companies may be reluctant to invest in studies that could limit the flexibility of immunotherapy administration.
However, researchers at Emory University are working on a single-center randomized trial with metastatic melanoma patients to determine the optimal time window for immunotherapy administration. While some oncologists remain unconvinced, patient awareness of these findings is increasing, with some actively requesting earlier infusion times.
“There are definitely people who are interested in the field,” said Dr. Matthew McMillan, a radiation oncology researcher at Memorial Sloan-Kettering Cancer Center.
Conclusion
While emerging data suggests a strong correlation between immunotherapy timing and improved survival outcomes, more research is needed before clinical guidelines can be adjusted. Until then, logistical challenges and funding limitations remain major hurdles in implementing time-based cancer treatment on a larger scale.
Disclaimer: This article is for informational purposes only and should not be considered medical advice. Patients should consult their oncologists before making any decisions regarding their treatment schedules.
