This would be an open label, single arm, single centre, phase II study designed to evaluate the efficacy of 177Lu-DOTA0-Tyr3-Octreotate in Metastatic NPC.~Patients will first need to go for a 68Ga-DOTATATE scan to determine if they are suitable for 177Lu-DOTA0-Tyr3-Octreotate therapy. A'Hern single stage phase II design (A'Hern, 2001) will be used for conducting the trial. The null hypothesis that the true PFS rate at 6 months is 10% will be tested against the alternate hypothesis of 25%. A total number of 25 patients will be recruited. If there are 5 or more patients who are alive and progression free among these 25 patients at 6 months, we reject the null hypothesis and claim that the treatment is promising.~The design controls the type I error rate at 9.8% and yields a power of 78.6% when the true PFS rate at 6 months is 25%. The first 5 patients will receive 180mCi of 177Lu-DOTA0-Tyr3-Octreotate for the first cycle followed by 200mCi for the remaining 3 cycles if there are no > Grade 2 toxicities after the first cycle. If there are >G2 toxicities, the remaining cycles will proceed at 180mCi. A safety review will be done after the first 5 patients. If there are no significant toxicities, the remaining patients will receive 200mCi for 4 cycles. If there are significant toxicities in patients receiving 200mCi for the 2nd to 4th cycle, the remaining patients will receive 180mCi for 4 cycles. If there are significant toxicities in patients receiving 180mCi for the 2nd to 4th cycle, the remaining patients will receive 160mCi for 4 cycles. Dosimetry scans will be done after each cycle of 177Lu-DOTA0-Tyr3-Octreotate at 1h and 96h. Safety and tolerability of 177LuDOTA0-Tyr3-Octreotate will be assessed for the duration of study treatment.~FDG PET/CT scan and 68Ga-DOTATATE scan will be performed at baseline and after cycle 1 (week 4) and cycle 4 (week 28). CT scans will be done at week 12, 24, then 3-monthly starting from week 40. 177Lu-DOTA0-Tyr3-Octreotate treatment will be continued until progression of disease, unacceptable toxicity, or another discontinuation criterion is met. In the case of toxicity, dose adjustment is permitted. A treatment cycle is eight weeks (56 days) and will be repeated without therapy interruption for 4 cycles unless there is dose limiting toxicities.
This study is the first phase II study of 177Lu-DOTA0-Tyr3-Octreotate in metastatic NPC. Patients whom have failed 2 or more lines of therapy or exhausted standard therapy and are avid on 68Ga-DOTATATE imaging will be eligible to receive up to 4 cycles of 177Lu-DOTA0-Tyr3-Octreotate. The primary outcome will be progression free survival at 6 months.