Canada's Drug Agency (CDA, formerly CADTH) has issued a Time-Limited Reimbursement (TLR) recommendation for ENHERTU (trastuzumab deruxtecan), marking the first such recommendation for gastric cancer treatment in the country. This decision accelerates access for adult patients with unresectable, locally advanced or metastatic HER2-positive gastric or gastroesophageal junction (GEJ) adenocarcinoma who have previously received a trastuzumab-based regimen.
In a parallel development, AstraZeneca, Daiichi Sankyo, and the pan-Canadian Pharmaceutical Alliance (pCPA) have signed a Letter of Intent through the recently introduced Temporary Access Process (pTAP). These combined processes are expected to make ENHERTU available to eligible patients approximately two years faster than traditional reimbursement pathways.
"As early participants in these innovative drug reimbursement processes, AstraZeneca and Daiichi Sankyo are pleased to accelerate access to innovative treatments for Canadian patients, particularly in areas of great unmet need, such as HER2+ gastric cancer," said Gaby Bourbara, President of AstraZeneca Canada.
Accelerated Access Through Innovative Pathways
The TLR and pTAP processes represent new mechanisms designed specifically for medications showing early promise that have received conditional regulatory approval. These pathways allow patients to access potentially life-extending treatments while confirmatory clinical trials are still ongoing.
Fatih Yedikardeş, Country Manager at Daiichi Sankyo Canada, emphasized the companies' commitment to patient access: "Daiichi Sankyo and our partners at AstraZeneca are committed to ongoing collaboration with the HTA bodies to identify and leverage new ways to make medicines accessible to patients across the country as fast as possible following Health Canada approval."
Without these accelerated pathways, patients would have had to wait for the completion and review of the Phase III DESTINY-Gastric04 study before gaining access to ENHERTU.
Conditional Approval Based on Phase II Data
Health Canada granted a Notice of Compliance with conditions (NOC/c) for ENHERTU on January 17, 2025. This conditional approval was based on results from the DESTINY-Gastric02 and DESTINY-Gastric01 Phase II trials.
The confirmatory Phase III trial, DESTINY-Gastric04, is currently underway globally. This randomized, open-label trial is evaluating the efficacy and safety of trastuzumab deruxtecan (6.4 mg/kg) versus ramucirumab and paclitaxel in patients with HER2-positive (IHC 3+ or IHC 2+/ISH+) unresectable and/or metastatic gastric or GEJ adenocarcinoma whose disease has progressed on or after a trastuzumab-containing regimen.
Addressing a Significant Unmet Need
Gastric cancer represents a substantial health burden globally and in Canada. It is the fifth most common cancer worldwide and the fourth leading cause of cancer mortality, with a dismal five-year survival rate of just 7.5% for metastatic disease. In Canada specifically, approximately 4,200 people will be diagnosed with gastric cancer this year, and around 2,000 will die from the disease.
About ENHERTU
ENHERTU is a HER2-directed antibody-drug conjugate (ADC) developed using Daiichi Sankyo's proprietary DXd technology. The drug consists of a HER2 monoclonal antibody attached to a topoisomerase I inhibitor payload (an exatecan derivative) via a stable tetrapeptide-based cleavable linker.
The drug's mechanism of action allows it to deliver targeted therapy to HER2-expressing cancer cells, potentially offering improved outcomes for patients with limited treatment options.
Collaborative Development
ENHERTU represents a successful global collaboration between Daiichi Sankyo and AstraZeneca, which began in March 2019. Under this partnership, both companies jointly develop and commercialize ENHERTU globally, except in Japan where Daiichi Sankyo maintains exclusive rights. Daiichi Sankyo is responsible for the manufacturing and supply of the medication.
This landmark reimbursement decision highlights Canada's evolving approach to providing earlier access to promising cancer therapies, particularly in disease areas with significant unmet needs. For patients with HER2-positive gastric cancer who have limited treatment options, this accelerated access could represent a meaningful advancement in their care.
