Purpose: To centrally assess the safety, efficacy, and 6-year follow-up of recombinant adenovirus-p53 (rAd-p53) combined with radiotherapy (RT) for patients with nasopharyngeal carcinoma (NPC).
Patients and methods: A randomized controlled clinical study on rAd-p53 combined with RT in 42 patients with NPC was compared with a control group of 40 patients with NPC treated with RT alone. In the group receiving rAd-p53 combined with RT, rAd-p53 was intratumorally injected once a week for 8 weeks. Concurrent RT (70 Gy in 35 fractions) was given to the nasopharyngeal tumor and neck lymph node. Patients and tumors were monitored for adverse events and responses.
Results: rAd-p53-specific p53 mRNA was detected in postinjection of rAd-p53 biopsies from 16 (94.1%) of 17 patients. Upregulation of p21/WAF1 and Bax and downregulation of vascular endothelial growth factor were observed in postinjection tumor biopsy. Complete response rate in the group receiving rAd-p53 combined with RT was observed at 2.73 times that of the group receiving RT alone (66.7% v 24.4%). Six-year follow-up data showed that rAd-p53 significantly increased the 5-year locoregional tumor control rate by 25.3% for patients with NPC treated with irradiation (P = .002). The 5-year overall survival rate and 5-year disease-free survival rate of the group receiving rAd-p53 combined with RT were 7.5% (P = .34) and 11.7% (P = .21) higher than those of the group receiving RT alone. No dose-limiting toxicity or adverse events appeared, except for transient fever after rAd-p53 administration.
Conclusion: In patients with NPC, rAd-p53 was safe and biologically active. Our results indicated that rAd-p53 improves radiotherapeutic tumor control and survival rate in patients with NPC.