Ivonescimab plus chemotherapy cuts disease progression risk by 40% in first-line squamous NSCLC, outperforming PD-1 rival in Akeso’s HARMONi-6 trial

In a major clinical milestone that could reshape global standards of care in lung cancer, Akeso Inc. (HKEX: 9926) has reported that its bispecific antibody ivonescimab, when combined with chemotherapy, reduced the risk of disease progression or death by about 40 percent compared with tislelizumab plus chemotherapy in first-line treatment of patients with advanced squamous non-small cell lung cancer (NSCLC). The data, derived from the company’s pivotal HARMONi-6 Phase III study, position ivonescimab as one of the most clinically promising challengers to current PD-1-based regimens in China—and potentially worldwide.

The randomized, head-to-head trial compared ivonescimab, a dual PD-1 and VEGF inhibitor, with the established PD-1 inhibitor tislelizumab. According to Akeso’s statement, patients receiving ivonescimab plus chemotherapy achieved significantly longer progression-free survival (PFS) than those treated with tislelizumab plus chemotherapy. The reported hazard ratio of approximately 0.6 translates to a 40 percent reduction in the risk of disease progression or death, a result that was statistically significant with a p-value below 0.0001.

Why ivonescimab’s bispecific design could change how squamous NSCLC is treated globally

Ivonescimab (also known as AK112) belongs to a new class of bispecific antibodies designed to simultaneously block two key cancer-promoting pathways: the PD-1 immune checkpoint and the VEGF angiogenic signaling axis. The rationale behind this dual targeting is to combine the immune activation seen with checkpoint blockade and the vascular normalization benefits of VEGF inhibition, effectively attacking tumor growth from two fronts.

Squamous NSCLC, which accounts for about 25 to 30 percent of all NSCLC cases, has long presented treatment challenges because angiogenesis inhibitors such as bevacizumab have been associated with bleeding risks in this histology. Ivonescimab’s ability to achieve meaningful efficacy without increasing severe bleeding rates has been interpreted by several oncology analysts as a sign of pharmacologic balance—allowing VEGF inhibition with reduced toxicity.

The HARMONi-6 study enrolled 532 patients across 66 sites in China, randomizing them to receive either ivonescimab or tislelizumab plus platinum-doublet chemotherapy. Investigators reported improvements across all predefined subgroups, including PD-L1-negative patients, underscoring the potential for broader applicability across biomarker profiles. No new safety signals emerged, and rates of grade 3 or higher bleeding events remained comparable between treatment arms.

Clinical experts cited by Chinese oncology outlets suggested that ivonescimab’s performance represents “the first time a bispecific antibody has outperformed a PD-1 backbone in a front-line squamous NSCLC setting,” marking what they described as a turning point for China’s immuno-oncology landscape.

How the HARMONi-6 results compare with other PD-1 and PD-L1 inhibitor regimens in first-line squamous NSCLC

For nearly a decade, PD-1 inhibitors such as pembrolizumab, nivolumab, and tislelizumab have dominated the first-line setting in squamous NSCLC, typically in combination with platinum chemotherapy. Despite these advances, median progression-free survival with PD-1 plus chemo has plateaued in the 6- to 8-month range for many patients.

By contrast, Akeso reported median PFS values exceeding 11 months for ivonescimab plus chemo, representing one of the strongest efficacy signals ever observed in this histology. These data were simultaneously presented at the 2025 European Society for Medical Oncology (ESMO) Congress and published in The Lancet, suggesting rapid academic validation and significant clinical interest.

The company emphasized that the PFS benefit was consistent across PD-L1 expression strata and that objective response rates improved meaningfully versus tislelizumab. Overall survival data are not yet mature, but Akeso expects to share interim OS results in 2026. If these survival advantages persist, ivonescimab could become the first immunotherapy from a Chinese biotech to challenge established Western PD-1 standards head-on.

Analysts covering Asian biotech equities noted that these findings are particularly disruptive because tislelizumab itself was once considered one of the strongest PD-1 therapies in China. Ivonescimab’s superiority could therefore reset expectations across domestic oncology pipelines and accelerate international licensing discussions.

What Akeso’s regulatory progress and investor sentiment reveal about its near-term trajectory

Shortly after the HARMONi-6 announcement, the China National Medical Products Administration accepted Akeso’s supplemental new drug application (sNDA) for ivonescimab plus chemotherapy as a first-line treatment for advanced squamous NSCLC. The agency is prioritizing review under its expedited pathway for innovative drugs with demonstrated clinical superiority.

On the Hong Kong Stock Exchange, Akeso Inc. (HKEX: 9926) saw its shares rally following the trial readout, reflecting heightened investor confidence in the company’s dual-immune portfolio. Market watchers interpreted the 40 percent risk reduction headline as a signal of sustainable differentiation and a potential commercial inflection once regulatory approval is granted.

Equity analysts from several regional brokerages pointed out that the HARMONi-6 data could catalyze additional partnerships or co-development deals, especially as Akeso advances other bispecifics such as ivonescimab in combination with its PD-1/CTLA-4 candidates. Institutional sentiment appears cautiously optimistic, supported by an expanding body of evidence that Chinese-developed biologics are reaching Western efficacy benchmarks faster than expected.

Nevertheless, investors remain attentive to global validation, noting that Akeso will likely need an ex-China confirmatory program to attract multinational partners or potential FDA consideration. Analysts also observed that competition within China’s oncology market remains intense, with more than a dozen PD-1-based regimens already available.

How global oncologists and policymakers are evaluating the implications for standard of care

The HARMONi-6 results are being closely examined by oncologists worldwide as a possible precursor to a new standard of care in first-line squamous NSCLC. Global experts cited in independent analyses said that if ivonescimab’s efficacy translates to non-Asian populations with comparable safety, it could prompt Western regulators to reconsider current treatment hierarchies dominated by single-target PD-1 or PD-L1 inhibitors.

Akeso’s bispecific design also aligns with a broader industry trend toward “polyfunctional” immunotherapies—agents engineered to engage multiple immune pathways at once. Large pharmaceutical firms including Roche, AstraZeneca, and Merck are exploring similar constructs, but Akeso’s HARMONi-6 success gives it a first-mover advantage in clinically validated bispecific immuno-oncology.

Policy analysts in China have noted that the country’s emphasis on homegrown biologics could further accelerate reimbursement approvals. If accepted, ivonescimab would become the first PD-1/VEGF bispecific approved for any indication, potentially altering pricing dynamics across the entire immunotherapy segment.

Industry observers have framed the development as symbolic of China’s maturing biotech ecosystem—one capable not only of imitation but genuine innovation. Should Akeso secure regulatory clearance and maintain performance consistency in broader populations, the company could move from domestic leader to global contender in immuno-oncology.

What the results signal for patients, investors, and the competitive landscape ahead

The emergence of ivonescimab marks a pivotal shift for both clinicians and investors monitoring oncology innovation from Asia. Clinically, it represents proof that dual-checkpoint inhibition can yield additive benefits without compounding toxicity. Strategically, it demonstrates that Chinese biopharma companies are now setting new efficacy benchmarks rather than chasing Western comparators.

Patient advocates have highlighted that the ~40 percent risk reduction observed in HARMONi-6 translates into several additional months of disease control—a meaningful improvement in a cancer subtype long associated with poorer outcomes. For investors, the trial offers a new valuation anchor for Akeso’s bispecific pipeline, which spans multiple solid-tumor and hematologic indications.

The HARMONi-6 success highlights a turning point in global immunotherapy development—an era where the next oncology breakthrough could emerge as readily from Shenzhen or Shanghai as from Boston or Basel. For Akeso, this milestone validates nearly a decade of research into bispecific antibody engineering and may unlock broader opportunities in the global oncology pipeline, particularly in regions seeking cost-effective, next-generation checkpoint inhibitors. Market watchers have already begun speculating on potential licensing or co-commercialization partnerships with Western pharmaceutical firms, viewing ivonescimab as a bridge between Chinese biotech innovation and international clinical standards. For patients, it reinforces the possibility that first-line treatment for squamous NSCLC may soon become not just more effective but more accessible—marking an encouraging step toward a new, globally inclusive model of cancer care.