Toripalimab with Fruquintinib as the third-line treatment for refractory advanced metastatic colorectal cancer: Results of a single-arm, single-center, prospective, phase II clinical study.

Abstract

e15573 Background: The most effective treatment of immune checkpoint inhibitors (ICIs) is restricted in microsatellite instability (MSI-H) subsets of advanced colorectal cancer, but MSI-H only accounts for 4-5% among them. Currently, Fruquintinib/ Regorafenib is the standard third-line treatment for metastatic colorectal cancer (mCRC) with microsatellite stable (MSS), which efficacy remains limited in pre-clinical trials. According to the published literature, ICIs has little efficacy in the treatment of refractory advanced mCRC patients with MSS. However, there may be a good synergistic mechanism in the combination of ICIs and anti-VEGFR drugs, which can improve the tumor microenvironment (TME). Our study aimed to evaluate the efficacy and safety of Fruquintinib plus Toripalimab as third-line treatment for refractory advanced mCRC. Methods: This was a single-arm, single-center, phase II clinical trial with 30 patients. Pts received toripalimab (240mg, i.v., Q3W), combined with Fruquintinib (5mg, p.o., 3 weeks on/ 1 week off) until the disease progresses/unacceptable toxicity or receiving the above two drugs as maintenance treatment. The primary endpoint was objective response rate (ORR); the secondary endpoints were disease control rate (DCR), 1-year progression-free survival (PFS) rate, overall survival (OS) and safety. Results: As of Feb 5, 2022, 24 mCRC pts (female: 29.2%, median age: 52.1 years) with ECOG PS ≤ 2 who failed to at least 2 previous lines of therapy containing fluoropyrimidine, oxaliplatin or irinotecan combined with Bevacizumab or Cetuximab were enrolled. The ORR was 16.7% (95% CI：59.7%-94.8%). The DCR was 54.1%, including 4 patients with PR and 9 patients with SD, respectively. 16 patients were alive and the study treatments for 6 patients were still ongoing. Median PFS was 6.0 months (95% CI：3.511-12.489), the 1-year PFS rate was 18%; median OS was 8.0 months (95% CI：1.452-10.548). Overall, 24 pts were enrolled for safety analysis, The most frequent treatment related adverse events were fatigue (50%), hepatocyte dysfunction (36.3%), hypertension (29.1%) and abdominal pain (27.0%). 6 patients (25%) experienced grade 3/4 TRAE (including hypertension, liver enzyme elevation, and immune-associated pneumonia). No treatment-related death was reported. TRAEs leading to either Fruquintinib or Toripalimab discontinuation occurred in 3 (12.5%) pts each. Conclusions: Fruquintinib plus Toripalimab showed certain efficacy and favorable safety profile in refractory advanced mCRC with MSS. It may provide a new choice for mCRC patients who are receiving third-line treatment. The results supported ongoing combined treatment in mCRC patients with MSS and more data will being updated subsequently. Clinical trial information: ChiCTR2000028965.

Efficacy, safety, and predictors of fruquintinib plus anti-programmed death receptor-1 (PD-1) antibody in refractory microsatellite stable metastatic colorectal cancer in a real-world setting: a retrospective cohort study

“…In two separate prospective, single-arm, single-center phase II clinical studies of fruquintinib combined with toripalimab, the median PFS was observed to be 5.98 and 6 months, respectively. The ORR were 21.5% and 16.7% ( 17 , 21 ). Yuan et al conducted a phase 2 prospective study (FRUIT trial) and discovered that fruquintinib in combination with tislelizumab (an anti-PD-1 Ab) and SBRT was effective as a late-line treatment for MSS mCRC patients.…”

Effectiveness of immune checkpoint inhibitors in combination with tyrosine kinase inhibitors in patients with advanced or metastatic colorectal carcinoma with either mismatch repair proficient or metastatic microsatellite stable disease: A systematic review and meta‑analysis

“…The study reported an ORR of 4.9% and a DCR of 50%. Furthermore, Ma et al (26) used a combination of toripalimab and fruquintinib, resulting in notable effectiveness: 4/18 patients in the final analysis exhibited partial responses, and 10/18 had stable disease. Nevertheless, further investigation is required to establish the effectiveness and safety of the combined administration of TKIs and ICIs.…”