June’s GI Rewind: CRC, Gastric Cancer See Several “Firsts” With FDA Review of Adjuvant IO, Global Approval of BRAF-Targeted and CAR T-Cell Therapies

The global gastrointestinal (GI) regulatory landscape continued to evolve throughout June 2026, with several notable regulatory actions across the United States and abroad.

This month featured the FDA's acceptance of a supplemental biologics license application (sBLA) for atezolizumab (Tecentriq)–based adjuvant therapy in patients with stage III mismatch repair–deficient (dMMR) or microsatellite instability–high (MSI-H) colon cancer.¹ June also saw the FDA issue a complete response letter (CRL) for an investigational gallium-68 edotreotide PET imaging kit for somatostatin receptor (SSTR)–positive neuroendocrine tumors (NETs) and grant fast track designation to a Claudin 18.2 (CLDN18.2)–targeted bispecific antibody for first-line HER2-negative metastatic gastric cancer.²˒³

Outside the United States, the European Union added an encorafenib (Braftovi)–based regimen to its arsenal for BRAF V600E–mutant metastatic colorectal cancer (mCRC); Japan approved a circulating tumor DNA (ctDNA) assay for CRC; and China's National Medical Products Administration (NMPA) approved the world’s first CAR T-cell therapy for solid tumors.^4,5,6

Read on for the full month in review.

FDA Updates

LNTH-2501 PET Imaging Kit Receives CRL From FDA for SSTR-Positive NETs

On June 26, the FDA issued a CRL to the new drug application (NDA) seeking approval of LNTH-2501, an investigational radioactive diagnostic kit intended for the preparation of gallium-68 edotreotide injection for PET imaging to localize SSTR-positive NETs in adult and pediatric patients.²

The diagnostic accuracy of gallium-68 edotreotide in SSTR-positive NETs was demonstrated in a phase 1/2 study (NCT01619865) comparing gallium-68 edotreotide PET/CT with standard indium 111-pentetreotide (Octreoscan) SPECT plus high-resolution, contrast-enhanced CT, and a phase 2 trial (NCT01869725) comparing the diagnostic accuracy of gallium-68 edotreotide PET/CT with standard indium 111-pentetreotide imaging plus contrast-enhanced CT or MRI.

According to the FDA, the CRL was issued because manufacturing conditions at a third-party production facility remained unresolved at the time of review. Importantly, the agency did not cite any concerns about the data supporting the NDA, nor did it raise concerns regarding the safety or efficacy of LNTH-2501. Resolution of the manufacturing observations is required before the NDA can be approved, leaving the application's regulatory path dependent on facility remediation rather than additional clinical evidence.

Adjuvant Atezolizumab Regimen Under FDA Review for Stage III dMMR/MSI-H Colon Cancer

On June 11, the FDA accepted and granted priority review to an sBLA seeking the approval of atezolizumab and atezolizumab/hyaluronidase-tqjs (Tecentriq Hybreza) in combination with chemotherapy as adjuvant treatment for patients with stage III dMMR or MSI-H colon cancer following surgical resection.¹

The application is supported by results from the phase 3 Alliance ATOMIC trial (NCT02912559), in which the addition of atezolizumab to modified fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) reduced the risk of disease recurrence or death by 50% compared with chemotherapy alone (HR, 0.50; 95% CI, 0.35-0.73; P < .001).

The FDA assigned the application a Prescription Drug User Fee Act target action date of October 9, 2026. If approved, the regimen would become the first immunotherapy-based adjuvant treatment available for this biomarker-defined patient population.

FDA Grants Fast Track Designation to Givastomig in First-Line HER2-Negative Metastatic Gastric Cancer

On June 16, the FDA granted fast track designation to the investigational bispecific antibody givastomig (TJ033721/ABL111) for the first-line treatment of patients with HER2-negative gastroesophageal adenocarcinomas.³

The designation was supported by clinical activity observed in an ongoing phase 1b trial (NCT04900818) evaluating givastomig-based therapy in advanced solid tumors.⁷ In the dose-expansion phase, givastomig produced an objective response rate (ORR) of 75% in evaluable patients across the 8 mg/kg and 12 mg/kg dose levels (n = 52). Responses were seen across a wide range of PD-L1 and CLDN18.2 expression levels and were durable. The agent was tolerable in combination with chemoimmunotherapy, without dose-dependent toxicity.

Of note, following a productive type B meeting in March 2026, the FDA confirmed that the investigational CLDN18.2 x 4-1BB bispecific antibody is eligible for an accelerated regulatory route in first-line HER2-negative, CLDN18.2-positive, and PD-L1–positive gastric and gastroesophageal cancer.

Global Updates

European Commission Approves First BRAF-Targeted Regimen in First-Line BRAF V600E–Mutant mCRC

On June 22, 2026, the European Commission approved encorafenib in combination with cetuximab (Erbitux) and fluorouracil, leucovorin, and oxaliplatin (FOLFOX) for the first-line treatment of adult patients with BRAF V600E–mutant mCRC.⁴

The decision was supported by findings from the phase 3 BREAKWATER trial (NCT04607421), which demonstrated statistically significant improvements in ORR, progression-free survival (PFS), and overall survival with encorafenib plus cetuximab and mFOLFOX6 compared with standard chemotherapy. The regimen reduced the risk of death by 51% compared with chemotherapy with or without bevacizumab (Avastin), supporting its use as a new first-line standard of care for patients with BRAF V600E–mutant mCRC.

Signatera Becomes First MRD-Detection Test Approved in Japan

Also on June 24, Signatera received regulatory approval from Japan’s Pharmaceuticals and Medical Devices Agency (PMDA) for patients with CRC in the adjuvant setting, making Signatera the first PMDA-approved minimal residual disease (MRD) test.⁵

Regulatory approval was supported by positive evidence from GALAXY, an observational arm of the CIRCULATE-Japan study (UMIN000039205). The study demonstrated that patients who test MRD-positive after surgery derive significant benefit from adjuvant chemotherapy, while those who test MRD-negative derive no benefit from adjuvant chemotherapy. With analysis of 2,240 samples, this is one of the largest and most comprehensive prospective studies of MRD testing in resectable CRC.

China's NMPA Approves First CAR T-Cell Therapy for Solid Tumors in CLDN18.2-Positive Gastric/GEJ Cancer

On June 26, 2026, China's NMPA approved satricabtagene autoleucel (satri-cel) for the treatment of patients with CLDN18.2-positive, HER2-negative advanced gastric or GEJ adenocarcinoma who have experienced disease progression following at least 2 prior lines of therapy.⁶ The decision marks the world's first regulatory approval of a CAR T-cell therapy for the treatment of a solid tumor and establishes a new therapeutic modality for advanced gastric cancer.

The approval was based on data from a phase 2 study (NCT04581473). At a median follow-up of 9.07 months (95% CI, 6.21-13.01) in the satri-cel arm (n = 104) and 3.45 months (95% CI, 2.89-not estimable) in the treatment of physician's choice arm (n = 52), satri-cel reduced the risk of disease progression or death by 63%. The median PFS was 3.25 months (95% CI, 2.86-4.53) compared with 1.77 months (95% CI, 1.61-2.04), respectively (HR, 0.37; 95% CI, 0.24-0.56; one-sided log-rank P < .0001). Grade 3 or higher treatment-emergent adverse effects were reported in 99% of evaluable patients receiving satri-cel (n = 88) compared with 63% of patients treated with physician's choice therapy (n = 48).

References

1. Flaherty C. FDA grants priority review to atezolizumab plus chemotherapy for stage III dMMR colon cancer. OncLive. June 11, 2026. Accessed July 1, 2026.https://www.onclive.com/view/fda-grants-priority-review-to-atezolizumab-adjuvant-regimen-for-stage-iii-dmmr-c
2. Wahner A, Flaherty C. FDA issues CRL to PET diagnostic imaging kit for gallium-68 edotreotide in SSTR-positive NETs. OncLive. June 29, 2026. Accessed July 1, 2026. https://www.onclive.com/view/fda-issues-crl-to-pet-diagnostic-imaging-kit-for-gallium-68-edotreotide-in-sstr-nets
3. NovaBridge Biosciences receives FDA fast track designation for givastomig in first-line HER2-negative metastatic gastric cancer. News release. NovaBridge Biosciences. June 16, 2026. Accessed July 1, 2026.https://www.novabridge.com/news-releases/news-release-details/novabridge-biosciences-receives-fda-fast-track-designation
4. Laboratoires Pierre Fabre receives European Commission approval for Braftovi (encorafenib) in combination with cetuximab and FOLFOX (fluorouracil, leucovorin, and oxaliplatin) for first-line treatment of adult patients with BRAFV600E-mutant metastatic colorectal cancer. News release. Pierre Fabre Laboratories. June 22, 2026. Accessed July 1, 2026.https://www.prnewswire.com/news-releases/laboratoires-pierre-fabre-receives-european-commission-approval-for-braftovi-encorafenib-in-combination-with-cetuximab-and-folfox-fluorouracil-leucovorin-and-oxaliplatin-for-the-first-line-treatment-of-adult-patients-with-b-302806336.html
5. Signatera receives regulatory approval in Japan for colorectal cancer. News release. Natera. June 24, 2026. Accessed July 1, 2026. https://investor.natera.com/news/news-details/2026/Signatera-Receives-Regulatory-Approval-in-Japan-for-Colorectal-Cancer-51cd8b904/default.aspx
6. Ryan C. China’s NMPA approves first CAR T-cell therapy for CLDN18.2+, HER2– advanced gastric/GEJ adenocarcinoma. OncLive. June 22, 2026. Accessed July 1, 2026. https://www.onclive.com/view/china-s-nmpa-approves-first-car-t-cell-therapy-for-cldn18--2-her2-advanced-gastric-gej-adenocarcinoma
7. NovaBridge announces productive FDA Type B meeting on potential accelerated approval pathway for givastomig in gastric cancer. News release. NovaBridge Biosciences. March 16, 2026. Accessed July 1, 2026.https://www.novabridge.com/news-releases/news-release-details/novabridge-announces-productive-fda-type-b-meeting-potential
8. Ryan C. T-DXd wins EU approval for previously treated, HER2+ metastatic solid tumors. OncLive. June 29, 2026. Accessed July 1, 2026. https://www.onclive.com/view/t-dxd-wins-eu-approval-for-previously-treated-her2-metastatic-solid-tumors
9. World’s first CLDN18.2 ADC for regulatory review: Innovent Biologics announces IBI343 (arcotatug tavatecan) met primary endpoint in international phase 3 study in advanced refractory gastric cancer and NDA accepted by China NMPA. News release. Innovent Biologics. June 4, 2026. Accessed July 1, 2026.https://en.innoventbio.com/InvestorsAndMedia/PressReleaseDetail?key=601