A Durable Response after the Discontinuation of Nivolumab in an Advanced Gastric Cancer Patient

Extending the dosing intervals of nivolumab: model-based simulations in unselected cancer patients

BACKGROUND

Reducing nivolumab dose intensity could increase patients' life quality and decrease the financial burden while maintaining efficacy. The aims of this study were to develop a population PK model of nivolumab based on data from unselected metastatic cancer patients and to simulate extended-interval regimens allowing to maintain minimal effective plasma concentrations (MEPC).

METHODS

Concentration-time data (992 plasma nivolumab concentrations, 364 patients) were modeled using a two-compartment model with linear elimination clearance in Monolix software. Extended-interval regimens allowing to maintain steady-state trough concentrations (Cmin,ss) above the MEPC of 2.5 mg/L or 1.5 mg/L in >90% of patients were simulated.

RESULTS

Increasing 3-times the dosing interval from 240 mg every two weeks (Q2W) to Q6W and 2-times from 480 mg Q4W to Q8W resulted in Cmin,ss above 2.5 mg/L in 95.8% and 95.4% of patients, respectively. 240 mg Q8W and 480 mg Q10W resulted in Cmin,ss above 1.5 mg/L in 91.0% and 91.8% of patients, respectively. Selection of a 240 mg Q6W regimen would decrease by 3-fold the annual treatment costs compared to standard regimen of 240 mg Q2W (from 78,744€ to 26,248€ in France).

CONCLUSIONS

Clinical trials are warranted to confirm the non-inferiority of extended-interval compared to standard regimen.

A Case of Long-Term Survival with Recurrent Liver Metastases from Gastric Cancer Treated with Nivolumab

Introduction

Improvements in overall survival from advanced gastric cancer have recently been reported with nivolumab. However, few reports have described long-term survival after discontinuing treatment.

Case Presentation

A 67-year-old man diagnosed with advanced gastric cancer and abdominal aortic aneurysm initially underwent distal gastrectomy with D2 dissection. Histological examination revealed tub2 and T2N1M0 stage IIA. One month later, endovascular aneurysm repair was performed. Six weeks after gastrectomy, adjuvant chemotherapy with S-1 was started. Six months later, liver metastases were identified and liver segments S1 and S7 were resected. S-1 and oxaliplatin were added postoperatively, but multiple liver metastases recurred. Paclitaxel and ramucirumab, irinotecan, and docetaxel were administered. Liver metastases showed a temporary reduction in size, then enlarged again. Nivolumab was therefore administered and the liver metastases showed a significant reduction in size. The interval between doses gradually increased due to persistent general fatigue. At 28 months after starting nivolumab therapy, bronchitis and adrenal insufficiency appeared, so treatment was discontinued. As of 3.5 years after cessation of nivolumab immunotherapy, tumor regression continued to be maintained. The patient remains alive as of 8 years after recurrence of liver metastases.

Conclusion

We encountered a case in which the patient received nivolumab therapy for recurrent liver metastases from gastric cancer and survived long term after discontinuing treatment.

Successful treatment with nivolumab in a patient with unresectable oral squamous cell carcinoma following ineffective chemoradiotherapy

Key clinical message

Nivolumab has been clinically successful in prolonging the overall survival of patients with recurrent and metastatic head and neck cancer, complete remission is rare. Synergistic combinations of immunotherapy and conventional cancer treatments, such as radiotherapy or chemotherapy, are likely to be the most viable strategies for improving patient responses.

Abstract

Immune checkpoint inhibitors have revolutionized recurrent, metastatic oral cancer treatment; however complete remission in advanced stages is unusual. We present a case of complete remission of advanced oral squamous cell carcinoma for >4 years in a 64-year-old Japanese woman, that responded poorly to chemoradiotherapy but well to subsequent nivolumab treatment.

Discontinuation of anti‑programmed cell death protein 1 immune checkpoint inhibition after complete remission in head and neck squamous cell carcinoma: A case report and literature review

Programmed cell death protein 1 (PD-1) inhibition plays a central role in the current treatment of recurrent or metastatic head and neck squamous cell carcinoma (R/M-HNSCC). Some patients achieve a durable response, and even complete remission (CR) is possible, though it occurs rarely. In cases of durable CR, there are no guidelines regarding a possible discontinuation of immunotherapy. Since clinical experience on this issue is limited, the present study reported on a case of a durable CR following discontinuation of PD-1 inhibition in R/M-HNSCC and additionally presented an overview on the current literature. The present study reported on a case of CR of recurrent oropharyngeal cancer after four cycles of PD-1 monotherapy with Nivolumab. The therapy was discontinued after overall 46 cycles. Even after 3 more years of follow-up, there was no sign of tumor recurrence. Overall, according to reports from the literature, CR seems to be an indicator for durable disease control after therapy discontinuation. Since data on therapy termination is rare, decisions about when to stop successful immunotherapy in R/M-HNSCC have to be made individually for each patient.

Immune-related adverse events associated with immune checkpoint inhibitors for advanced gastric and gastroesophageal junction cancer: A meta-analysis

BACKGROUND

Immune checkpoint inhibitors (ICIs) have shown promising efficacy in treatment and clinical management of advanced gastric and gastroesophageal junction cancer. However, the inhibitors also cause immune-related adverse events (irAEs). The current systematic review and meta-analysis study aimed to investigate the incidence and nature of irAEs caused by ICIs.

AIM

To investigate the incidence and nature of irAEs in advanced gastric and gastroesophageal junction cancer.

METHODS

This systematic review was registered with PROSPERO (Reg. number: CRD42020152291). Data included in this study were collected from patients diagnosed with advanced gastric cancer or gastroesophageal junction cancer and treated with ICIs. A systematic literature search was conducted using the PubMed, EMBASE, and Cochrane Library databases. Meta-analysis was carried out using the single sample rate method. Synthesis and analysis of the data was conducted using Stata/SE and Review Manager Software.

RESULTS

The patients enrolled in the present study included 14 patients from 14 case reports, 326 patients from 6 case series, and 1249 patients from 8 clinical trials. It was found that the overall incidence of irAEs was 16% [95% confidence interval (CI): 11-20] for all grades and 3% (95%CI: 2-4) for the severe grade. It was evident that the incidence of irAEs varied with the type of inhibitor and organs. A comparative study of the anti-programmed cell death receptor-1 (PD-1) and anti-programmed death receptor-ligand 1 (PD-L1) treatments showed that the anti-PD-1 group had a higher overall incidence of irAEs (20%) as compared with that of the anti-PD-L1 group (13%). Results of this study showed that the endocrine system experienced the highest incidence of organ-specific irAEs (7.4%), including hypothyroidism, hyperthyroidism, thyroiditis, diabetes, and adrenal insufficiency, followed by gastroenterology (2.2%), pulmonology (1.8%), neurology (1.4%), dermatology (1.4%), hematology (0.8%), and hepatology (0.7%). In clinical trials, it was found that the incidence of death related to irAEs was 1% (95%CI: 0-2.0), whereby colitis and interstitial lung diseases were the leading causes of death.

CONCLUSION

It was evident that the incidence and nature of irAEs are both organ- and inhibitor-specific. The anti-PD-1 group had the highest incidence of all irAEs grades including the severe grades of irAEs. Early identification and management of irAEs allows clinical oncologists to effectively consider the pros and cons and hence enables them to strike a balance.

Transition of the PD‑1 occupancy of nivolumab on T cells after discontinuation and response of nivolumab re‑challenge

Although nivolumab is administered every two or four weeks, high programmed cell death-1 (PD-1) binding of nivolumab on T cells lasting for several months has been reported. A relationship between the PD-1 occupancy rate on T-cells and the efficacy of nivolumab is not yet fully understood. The present study used flow cytometric analyses to determine the time-dependence of PD-1 occupancy in five patients who discontinued nivolumab. The relationship between PD-1 occupancy at relapse and the efficacy of re-challenge was also studied. Occupancies after discontinuation were measured at a total of 32 points. The data indicated that it took 32.4 and 48.9 weeks to decrease occupancy by 50 and 70%, respectively. Subsequently, two patients had recurrence and were re-challenged with nivolumab. At that time, one patient had 70.8% occupancy while the other had 6.6%. Treatment was effective only for the patient with lower occupancy. Overall, the present study suggests that re-challenge with nivolumab may be efficacious in patients with low occupancy at recurrence.