NuCana Fortifies Global IP with European Patent for Cancer Drug

EDINBURGH, United Kingdom – September 30, 2026 – In the high-stakes arena of biopharmaceutical development, intellectual property is the ultimate currency. NuCana plc (NASDAQ: NCNA), an Edinburgh-based clinical-stage biopharmaceutical company, has just minted a highly valuable asset in this regard. The company announced today that the European Patent Office (EPO) has granted a critical composition-of-matter patent (EP 3683225) for its lead anti-cancer candidate, NUC-7738.

Currently being evaluated in the Phase 2 portion of a Phase 1/2 clinical study (NuTide:701), NUC-7738 is taking aim at one of oncology's most pressing challenges: PD-1 inhibitor-resistant metastatic melanoma. By securing this patent in Europe, NuCana has effectively closed the loop on a trilateral intellectual property moat that already includes the United States and China, cementing its commercial strategy across the world's most lucrative pharmaceutical markets.

Closing the Trilateral Moat: A Global IP Strategy

For clinical-stage biotechs, the composition-of-matter patent is the holy grail of intellectual property. Unlike method-of-use or manufacturing patents, which competitors can sometimes engineer around, a composition-of-matter patent protects the fundamental chemical structure of the drug itself. It guarantees that no other entity can make, use, or sell the exact compound without authorization.

The newly granted EP 3683225 expands NuCana's global patent estate for NUC-7738 to over 85 issued patents worldwide. This comprehensive coverage is essential not only for long-term commercialization but also for positioning the asset favorably in potential licensing deals or acquisition talks.

"We are delighted that the EPO has granted this important new patent, which further strengthens the intellectual property protection of NUC-7738 and reflects the strength and novelty of our science," said Hugh S. Griffith, NuCana’s Founder and Chief Executive Officer. "This composition-of-matter patent is a critical addition to our global patent estate for NUC-7738, which now spans over 85 issued patents worldwide, and builds upon similar composition-of-matter patents previously granted in both the United States and China. This underscores our commitment to protecting NUC-7738's long-term commercial potential across all major markets."

Furthermore, the European patent landscape offers additional layers of protection. Upon receiving marketing authorization, NuCana will be eligible to apply for Supplementary Protection Certificates (SPCs) in individual European countries. These certificates can extend the baseline 20-year patent term by up to five additional years to compensate for time lost during the lengthy clinical trial and regulatory approval processes, providing a highly lucrative tail of market exclusivity.

Tackling the PD-1 Resistance Hurdle

The scientific foundation of NUC-7738 rests on NuCana's proprietary ProTide technology. The drug is a transformation of 3'-deoxyadenosine, also known as cordycepin. While cordycepin has long demonstrated potent anti-cancer properties in preclinical settings, its clinical utility was historically derailed by rapid degradation in the bloodstream and poor cellular uptake. The ProTide technology bypasses these resistance mechanisms, allowing the drug to generate high intracellular levels of the active anti-cancer metabolite.

Once inside the cancer cell, NUC-7738 operates through a multifaceted mechanism, primarily by disrupting RNA polyadenylation. This disruption profoundly impacts gene expression and alters the tumor microenvironment. It is this specific alteration that researchers believe can resensitize "cold" tumors to immune checkpoint inhibitors.

The clinical implications are currently being tested in the NuTide:701 trial, where NUC-7738 is administered in combination with pembrolizumab (Keytruda) for patients with metastatic melanoma who have relapsed on or are refractory to prior PD-1 inhibitor therapy.

Interim data presented at recent European Society for Medical Oncology (ESMO) congresses have been highly encouraging. In a cohort of 12 heavily pre-treated patients, the combination therapy achieved a disease control rate of 75%, including two partial responses. Notably, one patient who had progressed on two prior lines of PD-1 therapy experienced a 55% reduction in tumor volume. Furthermore, seven of the 12 patients demonstrated a progression-free survival (PFS) of greater than five months—a significant deviation from the standard of care in this refractory population, which typically yields a median PFS of just two to three months.

The Competitive Landscape of Melanoma Therapeutics

The market opportunity for overcoming PD-1 resistance is staggering. While immune checkpoint inhibitors like Keytruda have revolutionized melanoma treatment, approximately 40% to 55% of patients exhibit primary resistance, and another 25% to 30% of initial responders eventually develop acquired resistance.

Consequently, the biopharmaceutical industry is locked in a fierce race to develop effective salvage therapies. The competitive landscape includes combination immunotherapies, such as pairing PD-1 inhibitors with CTLA-4 inhibitors or LAG-3 blockers like relatlimab. Oncolytic viruses are also making headway; for instance, the engineered herpes simplex virus RP1 (vusolimogene oderparepvec) recently secured accelerated FDA approval for advanced, refractory melanoma. Additionally, Tumor-Infiltrating Lymphocyte (TIL) therapies, such as lifileucel, have entered the fray for patients failing anti-PD-1 regimens.

Amidst this crowded field, NUC-7738's mechanism of action offers a distinct, differentiated approach. Rather than introducing a virus or engineering T-cells, NuCana's candidate targets the fundamental metabolic and epigenetic reprogramming of the tumor cells themselves. By reducing secreted forms of PD-L1 and inducing metabolic stress through RNA polyadenylation disruption, NUC-7738 fundamentally alters the immunosuppressive tumor microenvironment. Oncology researchers note that this unique pathway could provide a vital alternative for patients who do not respond to other emerging modalities, positioning NUC-7738 as a highly complementary asset in the oncologist's toolkit.

Funded to 2029: Balance Sheet Insulation Amid Market Volatility

Brilliant science and robust patents mean little without the capital to push them through the grueling clinical trial process. In an era where many clinical-stage biotechs are facing severe funding constraints and depressed valuations, NuCana’s financial footing provides a stark competitive advantage.

Alongside the patent announcement, the company reiterated that its current cash resources are expected to fund planned clinical and operational activities deep into 2029. As of June 30, 2026, NuCana reported cash and cash equivalents of £19.5 million. While this represents a strategic deployment of capital from previous quarters, the company has successfully optimized its burn rate. For the second quarter of 2026, NuCana reported a net loss of just £3.1 million, a dramatic reduction from the £24.1 million loss reported in the same period in 2025—largely due to the absence of prior non-cash warrant revaluation losses and streamlined administrative expenses.

This multi-year runway is a critical metric for investors. It insulates the company from the immediate need to execute dilutive financing rounds in a volatile equity market. More importantly, funding into 2029 ensures that NuCana has ample time and resources to complete the Phase 2 portion of the NuTide:701 study and potentially initiate subsequent registrational trials.

With the European composition-of-matter patent now in hand, a differentiated clinical asset showing early signs of efficacy in a high-need population, and a balance sheet fortified for the next three years, NuCana has assembled the foundational pillars required to navigate the complex journey from clinical promise to commercial reality.