2024 年ASCO 数据显示三联疗法在CLDN18.2 高/中表达的患者群体中（无论PD-L1 CPS表达水平如何）疗效尤为显著。创胜集团在近期美国ASCO 会上公布了TST001 三联疗法的一项I/II 期临床研究数据显示，初步疗效数据表明，与现有或新兴疗法的历史数据相比，TST001 加上 CAPOX 和 nivolumab 作为 G/GEJ 癌症患者的一线治疗组合，无论 PD-L1表达如何，都具有非常令人鼓舞的抗肿瘤活性。研究显示，CLDN18.2 高/中表达患者的mPFS 达到12.6 个月，客观缓解率（ORR）为68%。以CLDN18.2 极低/无表达的患者群体作为替代对照组，三联疗法降低了56%的疾病进展或死亡的风险（HR 为0.443）。与TS001 联合 CAPOX 相比，三联疗法不会增加安全性风险。According to the company's clinical data at the 2024 ASCO annual meeting, TST001 combined with navulizumab and CAPOX was expressed in CLDN18.2 high/medium, and the median progression-free survival (mPFs) of 80% of patients with PD-L1 CPS<5 was 12.6 months;
The results further validated the viability of the global phase III trial strategy for Osemitamab (TST001), which has been approved by the FDA and CDE;
Maintain the buy rating and raise the target price of DCF to HK$14.07.
ASCO data from 2024 showed that triple therapy was particularly effective in patients with high/medium expression of CLDN 18.2 (regardless of PD-L1 CPS expression level). Chuangsheng Group recently announced data from a phase I/II clinical study of the TST001 triple therapy at the ASCO conference in the US. Preliminary efficacy data showed that compared with historical data of existing or emerging treatments, TST001 plus CAPOX and nivolumab as a first-line treatment combination for G/GEJ cancer patients, regardless of PD-L1 expression, had very encouraging anti-tumor activity. The study showed that patients with high or medium expression of CLDN 18.2 reached a mPFS of 12.6 months and an objective response rate (ORR) of 68%. Using a group of patients with very low/no expression of CLDN 18.2 as an alternative control group, triple therapy reduced the risk of disease progression or death by 56% (HR of 0.443). Compared to TS001 combined with CAPOX, triple therapy does not increase safety risks.
Differentiated and significant clinical data support advancing the TS001 phase III study. Efficacy analysis results for 66 patients with known CLDN18.2 and PD-L1 expression levels showed a clear correlation between efficacy and CLDN18.2 expression levels. The MPFs of CLDN18.2 high/medium (H/M) expression/low expression (L) patients and/ remaining patients (R) were 12.6/8.5/6.7 months, respectively, and the ORR was 68%/61.1%/50%, respectively. Compared with the R group, the risk ratio (HR) of the H/M group and the R group was 0.443, and the PFS risk ratio of the HML group and the R group was 0.560. The company believes that the phase II trial results are an important milestone for TST001. The data showed significant anti-tumor activity, particularly in patients expressing CLDN 18.2 (H/M), including patients with PD-L1 CPS<5, which is consistent with its preclinical data and mechanistic hypotheses. These results further validate the company's strategy to advance the global Phase III trial, which has been approved by the FDA and CDE.
There is a significant difference from Astellas's Zolbetuximab: In March 2024, Japan's Ministry of Health, Labor, and Welfare approved Zolbetuximab in combination with chemotherapy to treat patients with advanced or recurrent gastric cancer that is CLDN18.2 positive and cannot be surgically resected. As the second-leading CLDN 18.2 monoclonal antibody in global development, the low correlation between TST001 and CLDN 18.2 expression levels will differentiate it from Zolbetuximab and place it in a more favorable competitive position after marketing.
Maintain the purchase rating and raise the target price to HK$14.07: Our two-stage DCF calculated an equity value of HK$5.7 billion, HK$14.07 per share (WACC: 9.8%, terminal growth rate: 2%).
Risk warning: 1) Uncertainty about financial prospects and financing; 2) Product approval or failure to commercialize; 3) Intellectual property protection.
