Ivonescimab

"*" indicates required fields The American Association for Cancer Research (AACR) gathered in San Diego, California, for the annual congress from April 17 to 22 in 2026 to report progress in cancer research and uncover discoveries in patient care. We look at highlights from the event, as Labiotech spoke to a few biotechs who presented data at AACR 2026. A major reveal was pharma giant Merck’s phase 1/2 trial data of its bispecific antibody called MK-2010. It managed to induce a 55% overall response rate (ORR) in previously untreated patients with PD-L1-positive non-small cell lung cancer (NSCLC). These patients were given 20 mg/kg once every three weeks. In those patients who had been previously treated, an 18% ORR was observed in the 20 mg/kg dose cohort and a 22% ORR in 30 mg/kg cohort. The side effects included hypertension and excess protein in the urine, which are not uncommon with VEGF inhibitor drugs. Merck’s candidate, which was initially developed by China-based biotech LaNova Medicines until the pharma giant acquired the company two years ago, is way behind other contenders of its kind in the clinic. VEGF inhibitor developers like BioNTech, Guangdong-based Akeso, and California-based Summit Therapeutics, are all in the race to get the next approval in the field. The Merck data announced at AACR 2026 is comparable to Akeso and Summit Therapeutics’ 50% ORR for ivonescimab and 47% ORR of BioNTech and Bristol Myers Squibb’s anti-VEGF drug pumitamig, as well as big pharma company Pfizer and Shanghai-based 3SBio’s 62% ORR for SSGJ-707 given at 10 mg/kg and 55% for the therapy dosed at 20 mg/kg in phase 2. Meanwhile, for patients with NSCLC data who are ROS1-positive – who make up about 1% to 2% of people with lung cancer – and for whom currently available tyrosine kinase inhibitors, the primary treatment for this indication do not work, there are no established options. At AACR 2026, Massachusetts-based Nuvalent presented data that signals that this could change. Nuvalent’s TKI zidesamtinib induced a 41% and 47% ORR who were previously given the TKIs Augtyro and Ibtrozi, respectively. This response had a median duration of response of 15.7 months – a measure of how long a patient’s cancer responds to treatment before it starts to grow again – in patients who were on Augtyro prior to the trial. “Zidesamtinib demonstrated clinically meaningful activity in this heavily pre-treated subgroup, including activity in tumors with the ROS1 G2032R resistance mutation and intracranial complete responses for patients with central nervous system (CNS) disease,” said Christopher Turner, chief medical officer at Nuvalent. “Importantly, this indicates that ROS1-positive NSCLC tumors may remain ROS1-dependent beyond treatment with repotrectinib (Augtyro) or taletrectinib (Ibtrozi) and we believe supports the potential for zidesamtinib, if approved, to provide a clinically meaningful treatment option for patients who have exhausted available therapies.” Various biotechs presented preclinical data in lung cancer as well, one of which was Maryland-based Ascentage Pharma. Ascentage’s APG-5918, a small-molecule that targets the EED protein, is being evaluated in small-cell lung cancer (SCLC), which is significantly more aggressive than NSCLC. In around 60% to 70% of cases, the cancer has spread throughout the body by the time of diagnosis. Ascentage claims that its candidate can epigenetically ‘prime’ small-cell lung cancer cells to respond better to topoisomerase I inhibitors so as to overcome chemoresistance. The candidate APG-5918 in combination with a chemotherapy demonstrated antitumor activity in a preclinical model without leading to significant body-weight loss, indicating favorable tolerability. Besides, advancements in pancreatic cancer research were spotlighted at AACR 2026. One of the most difficult cancers to treat, with about a 12% overall five-year survival rate, pancreatic cancers often gain resistance to chemotherapies. Early detection is rare and many tumors are inoperable at diagnosis. Phase 1 findings of a cancer vaccine unveiled by the Memorial Sloan Kettering Cancer Center showed that 87.5% of patients had a T-cell response. The personalized vaccine was given in combination with the monoclonal antibody atezolizumab as well as chemotherapy, and patients remained alive four to six years after surgery, compared to 25% of those who did not respond to the medication. The vaccine is deemed to be ‘personalized’ because it relies on taking the immune cells of the patients. These cells are then trained to attack specific mutations on their specific tumor cells. “These early results show this new immunotherapy approach has the potential to make a difference for one of the deadliest cancers,” said Vinod Balachandran, MD, the trial’s principal investigator and director of the Olayan Center for Cancer Vaccines at MSK. “The latest data from this small study suggest vaccines can meaningfully stimulate the immune system in some patients with pancreatic cancer – and these patients continue to do well years after vaccination.” Balachandran pointed out that mRNA vaccines could provoke the immune system to recognize and attack pancreatic cancer cells to reduce the risk of cancer recurring. “The results are encouraging,” said Balachandran. “They fuel our efforts to test personalized mRNA vaccines in more patients and more cancers.” The Memorial Sloan Kettering Cancer Center was also a key site for Revolution Medicine’s pancreatic cancer trial. It tested its KRAS inhibitor daraxonrasib, which targets mutations in the RAS gene to help control the growth of cells. KRAS mutations drive more than 90% of pancreatic cancer, and it is projected to be the second most deadly cancer in the U.S. by 2030. Patients had a 47% ORR in the ongoing clinical trial and progression-free survival was 7% at six months. The response rate – the number of patients with tumors that showed positive activity from the drug – was 47%. Eileen M. O’Reilly, a key investigator of the study, thinks that while larger trials need to be held to figure out how much better daraxonrasib is than chemotherapy, the study results are promising. “There is obviously a lot of optimism about this approach,” she said. “This drug’s effect on cancer appears to be at least comparable to chemotherapy and maybe even better.” Meanwhile, the hype around antibody-drug conjugates (ADC) continues. A new ADC developed by Shandong-based Qilu Pharmaceutical showed clinical benefit in a phase 1 study in platinum-resistant ovarian cancer. This group of patients face both a poor prognosis and limited treatment options. “ADCs can now deliver highly potent drugs more selectively to tumor cells while limiting systemic side effects including off-target toxicity. This has made them an increasingly attractive therapeutic option for treating tumors, where achieving sufficient efficacy without unacceptable side effects has been challenging in the past.” The candidate QLS5132 consists of a monoclonal antibody that targets the protein CLDN6 as well as a chemotherapy. The drug is designed to target the surface of ovarian cancer cells, where the CLDN6 protein is highly expressed. Across all dose levels, 18 patients experienced a 50% ORR and a disease control rate of 94.4%. Moreover, the phase 2 dosage did not result in cases of interstitial lung disease, ocular toxicity, oral mucositis, or febrile neutropenia – all of which are side effects linked to chemotherapies. Tao Zhu, chief physician who presented the study, called the findings “encouraging” and said that they support phase 3 trials of the ADC. ADCs have surely been gaining steam in recent times. According to Dongzhou Jeffery Liu, chief executive officer (CEO) of Heidelberg Pharma, located in Ladenburg, Germany, advances in linker technologies, payload design, and target selection are the reason for their growing popularity in the cancer care space. “ADCs can now deliver highly potent drugs more selectively to tumor cells while limiting systemic side effects including off-target toxicity. This has made them an increasingly attractive therapeutic option for treating tumors, where achieving sufficient efficacy without unacceptable side effects has been challenging in the past,” he said. The biotech’s lead candidate is the amanitin-based ADC pamlectabart tismanitin that is in early clinical studies for multiple myeloma. Liu told Labiotech that the findings from the clinical phase 1 dose escalation trial are “very encouraging,” with dose-dependent increases in ORRs. Heidelberg Pharma is pioneering the development of these antibody targeted amanitin conjugates, also known as ATACs. Amanitin is a toxin that is derived from green death cap mushrooms and is being utilized as a payload for cancer. Liu pointed out that ADCs are moving faster than ever and they have the potential to partially replace conventional chemotherapy in certain indications. “This shift is already translating into improved efficacy and better tolerability for patients. Looking forward, next generation ADCs offer the potential for better cancer treatment through improved targets, optimized ADC design, and novel payloads that can overcome resistance. Payload innovations such as amanitin, which acts independently of cell proliferation, open the door to deeper and more durable responses and may enable long‑term disease control, including in non-oncology therapy,” said Liu. Furthermore, London-based startup Promatix Biosciences plans to bring next-generation ADCs to the clinic. It is focused on targeting pairs of receptors expressed by tumor cells with minimal binding to tissues expressing only one of these receptors with the goal of causing tumor cell death while leaving healthy tissues untouched. Called the “AND gate” approach, it cannot be achieved by monospecific targeting of a tumor-associated antigen because in nearly all cases the tumor-associated antigen is also expressed in healthy tissue to some degree. Promatix’s chief scientific officer (CSO) Roy Petipher explained how the biotech’s candidate PBS293 works. It is directed to cell signaling factors EGFR and EphA2 to then bind to the tumor cells. When conjugated to a cytotoxic agent, this kills tumor cells with high potency but with much less impact on normal cells, supporting the thesis of higher therapeutic index. The candidate has been found to internalize in tumor cells more efficiently than the bivalent parental antibodies directed to EGFR and EpHA2 and is very effective in a preclinical model using KRAS. “There are a large number of bispecific ADCs in development, but these are not optimized for AND gate activity and target a relatively small number of known targets (about 11 currently). This approach lacks novelty, and the lack of AND gate optimisation will not lead to improved tumor selectivity and, in many cases, might compound safety issues,” said Petipher. “Improved tumor targeting requires the identification of tumor-associated antigens that are truly differentially expressed compared to healthy tissue.” Promatix’s proteomics approach allows these targets to be identified but, disappointingly, the number of single targets differentially expressed is very low, as only 24 in the cancers have been analyzed. However, identification of pairs of receptors that are differentially expressed has been much more successful, explained Petipher. “In the future, novel pairings targeted by bispecific antibodies optimized for AND gate activity are likely to lead to safer and more effective treatments and will dominant the ADC development landscape in coming years. There has been remarkable progress in identifying improved protease-sensitive linkers and payloads, but novel target identification has proceeded a much slower pace. This will change and the other key development will be the use of dual payloads to overcome acquired resistance,” said Petipher. Meanwhile, Planegg-based iOmx Therapeutics presented at AACR 2026. Its antibody IOMX‑0675 is first-in-class and designed to unlock both innate and adaptive immunity in solid tumors by simultaneously blocking the immunosuppressive receptors LILRB1 and LILRB2, while sparing closely related activating LILR family members. IOmx’s director of Early Pharmaceutical Development, Alexander N. Marziale, explained how the antibody works. “By intercepting LILRB1/2‑mediated immune suppression, which is driven by ligands such as HLA‑G, IOMX‑0675 restores cytotoxic T‑cell and NK‑cell function while reprogramming suppressive myeloid cells toward a pro‑inflammatory, tumor‑clearing phenotype. Preservation of activating LILRA signaling is expected to maintain beneficial immune tone that less selective approaches may compromise,” said Marziale. New immunotherapies like IOMX‑0675 have stirred the technological field. According to Marziale, the immunotherapeutics field has undergone a fundamental transformation, from early, largely empirical approaches based on broad immune stimulation to today’s precisely engineered, mechanism‑driven therapies. While initial efforts relied on non‑specific immune activation, such as cytokines or bacterial preparations, which demonstrated that the immune system could control cancer but were limited by toxicity and inconsistent efficacy, the introduction of monoclonal antibodies marked a major inflection point. “This progress culminated in immune checkpoint inhibitors, which validated the concept that releasing endogenous immune suppression could deliver durable clinical benefit across multiple solid tumor types and fundamentally change cancer treatment paradigms,” said Marziale. “Today, immunotherapy development is increasingly focused on overcoming resistance, expanding benefit beyond checkpoint‑responsive patients, and integrating biomarker‑guided approaches, signaling a shift from single‑agent breakthroughs toward next‑generation platforms designed for broader and more durable impact.” One such up-and-coming approach is Tacalyx’s technology targeting tumor-associated carbohydrate antigens (TACAs). These are abundantly expressed on cancer cells, where they regulate interactions between cells that drive malignant phenotypes such as invasion, angiogenesis and immunosuppression. TACAs remain consistently expressed even in tumors lacking actionable genomic alterations or after standard therapies fail, positioning them as a differentiated and largely untapped class of cancer-specific targets with potentially lower susceptibility to resistance. “Tacalyx combines complex synthetic carbohydrate chemistry with sophisticated antibody generation methods to reliably generate functional antibodies against TACAs. This unique approach allows for the development of highly selective therapies, such as ADCs and T-cell engagers, that target ‘undruggable’ glycans while minimizing off-target toxicity,” said Jean Engela, CEO of Tacalyx. Preclinically, its candidate TCX-201 delivered complete tumor regressions in colorectal and pancreatic models and was found to be safe. Plans to hit the clinic are scheduled for next year. Oncology partnerships were announced at AACR 2026, too, like PacBio and Covaris’ pact combining PacBio’s HiFi sequencing workflow with the Massachusetts-based sample manufacturer’s extraction technology, which is meant to allow researchers to revisit historical tumor samples and extract new genomic insights that were previously out of reach. “The PacBio and Covaris collaboration is focused on overcoming a long-standing barrier in cancer research: the inability to get high-quality genomic data from formalin-fixed, paraffin-embedded (FFPE) tumor samples. These archived samples represent decades of clinically annotated cancer data but have been largely inaccessible due to DNA damage and fragmentation caused during preservation,” said Amit Patel, senior director at Pacbio. Early studies using the PacBio-Covaris workflow across brain, kidney and uterine tumor samples uncovered around two to three times more large-scale DNA changes than standard methods alongside millions of smaller mutations and were able to link many of these changes together for the first time, Patel explained. “These insights will accelerate the identification of new biomarkers, inform more precise patient stratification and support the development of targeted therapies, advancing the development of more personalized and effective cancer treatment strategies,” said Patel. As biotechs and pharmas revealed promising data at AACR 2026 with more than 22,000 participants in attendance, it sets the tone for what’s to come in the next couple of years, with clinical readouts and drug candidates moving towards the clinic expected soon. Artificial intelligence and the future of antibody discovery