On June 3, 2023 Immunocore Holdings plc (Nasdaq: IMCR), a commercial-stage biotechnology company pioneering the development of a novel class of T cell receptor (TCR) bispecific immunotherapies designed to treat a broad range of diseases, including cancer, infectious diseases and autoimmune conditions, reported two posters at the 2023 American Society for Clinical Oncology meeting (Press release, Immunocore, JUN 3, 2023, View Source [SID1234632420]):

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A poster including an analysis of circulating tumor DNA (ctDNA) data from the Phase 3 KIMMTRAK (tebentafusp-tebn) trial in HLA-A*02:01 patients with metastatic uveal melanoma (mUM)
A trial-in-progress poster describing the design of the Phase 2/3 trial with tebentafusp as monotherapy and in combination with pembrolizumab in HLA-A*02:01 patients with previously treated advanced melanoma.
"We have shown that KIMMTRAK can deliver significant OS benefit to patients with metastatic uveal melanoma, regardless of best RECIST response. We have now validated ctDNA reduction as an early surrogate for OS in two separate clinical trials," said Koustubh Ranade, Vice President of Translational Medicine at Immunocore. "ctDNA reduction is one of the dual endpoints in our ongoing Phase 2/3 trial with tebentafusp in patients with previously treated advanced or metastatic melanoma."

In this analysis of the Phase 3 data for patients with best response of stable disease treated with KIMMTRAK, ctDNA reduction by week 9 was observed in 94% of patients (34/36) with detectable ctDNA at baseline, and this reduction was associated with longer overall survival (OS). These data were consistent with those presented at AACR (Free AACR Whitepaper) 2023 in showing that ctDNA reduction by week 9 was strongly associated with improved OS, even in patients with best RECIST response of progressive disease – further indicating that RECIST responses underestimate tebentafusp’s clinical benefits, and that early reduction in ctDNA may be a better predictor of long OS than radiographic response.

The Company also presented a trial-in-progress poster for the Phase 2/3 trial that has started randomizing patients with previously treated advanced melanoma, excluding uveal melanoma, who have progressed on an anti-PD1, received prior ipilimumab and, if applicable, received a BRAF kinase inhibitor. Patients will be randomized to one of three arms including tebentafusp, as monotherapy or in combination with an anti-PD1, and a control arm.

Poster details

Title: Early ctDNA reduction may identify patients with stable disease and long OS on tebentafusp
Presenting author: Dan Feng
Session: Melanoma/Skin cancers

Title: A Phase 2/3 trial in progress on tebentafusp as monotherapy and in combination with pembrolizumab in HLA-A*02:01+ patients with previously treated advanced, non-uveal melanoma
Presenting author: Diwakar Davar
Session: Melanoma/Skin cancers (Trial in Progress)

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About KIMMTRAK
KIMMTRAK is a novel bispecific protein comprised of a soluble T cell receptor fused to an anti-CD3 immune-effector function. KIMMTRAK specifically targets gp100, a lineage antigen expressed in melanocytes and melanoma. This is the first molecule developed using Immunocore’s ImmTAC technology platform designed to redirect and activate T cells to recognize and kill tumor cells. KIMMTRAK has been approved for the treatment of HLA-A*02:01-positive adult patients with unresectable or metastatic uveal melanoma in the United States, European Union, Canada, Australia, and the United Kingdom.

About Phase 3 IMCgp100-202 Trial
IMCgp100-202 (NCT03070392) is a randomized pivotal trial that evaluated overall survival (OS) of KIMMTRAK compared to investigator’s choice (either pembrolizumab, ipilimumab, or dacarbazine) in HLA-A*02:01-positive adult patients with previously untreated mUM. KIMMTRAK demonstrated an unprecedented OS benefit with a Hazard Ratio (HR) in the intent-to-treat population favoring KIMMTRAK, HR=0.51 (95% CI: 0.37, 0.71); p< 0.0001, over investigator’s choice (82% pembrolizumab; 13% ipilimumab; 6% dacarbazine).

IMPORTANT SAFETY INFORMATION

Cytokine Release Syndrome (CRS), which may be serious or life-threatening, occurred in patients receiving KIMMTRAK. Monitor for at least 16 hours following first three infusions and then as clinically indicated. Manifestations of CRS may include fever, hypotension, hypoxia, chills, nausea, vomiting, rash, elevated transaminases, fatigue, and headache. CRS occurred in 89% of patients who received KIMMTRAK with 0.8% being grade 3 or 4. Ensure immediate access to medications and resuscitative equipment to manage CRS. Ensure patients are euvolemic prior to initiating the infusions. Closely monitor patients for signs or symptoms of CRS following infusions of KIMMTRAK. Monitor fluid status, vital signs, and oxygenation level and provide appropriate therapy. Withhold or discontinue KIMMTRAK depending on persistence and severity of CRS.

Skin Reactions

Skin reactions, including rash, pruritus, and cutaneous edema occurred in 91% of patients treated with KIMMTRAK. Monitor patients for skin reactions. If skin reactions occur, treat with antihistamine and topical or systemic steroids based on persistence and severity of symptoms. Withhold or permanently discontinue KIMMTRAK depending on the severity of skin reactions.

Elevated Liver Enzymes

Elevations in liver enzymes occurred in 65% of patients treated with KIMMTRAK. Monitor alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total blood bilirubin prior to the start of and during treatment with KIMMTRAK. Withhold KIMMTRAK according to severity.

Embryo-Fetal Toxicity
KIMMTRAK may cause fetal harm. Advise pregnant patients of potential risk to the fetus and patients of reproductive potential to use effective contraception during treatment with KIMMTRAK and 1 week after the last dose.

The most common adverse reactions (≥30%) in patients who received KIMMTRAK were cytokine release syndrome, rash, pyrexia, pruritus, fatigue, nausea, chills, abdominal pain, edema, hypotension, dry skin, headache, and vomiting. The most common (≥50%) laboratory abnormalities were decreased lymphocyte count, increased creatinine, increased glucose, increased AST, increased ALT, decreased hemoglobin, and decreased phosphate.

For more information, please see full Summary of Product Characteristics (SmPC) or full U.S. Prescribing Information (including BOXED WARNING for CRS).

On June 3, 2023 Elevation Oncology, Inc. (Nasdaq: ELEV), an innovative oncology company focused on the discovery and development of selective cancer therapies to treat patients across a range of solid tumors with significant unmet medical needs, together with CSPC Pharmaceutical Group Limited (CSPC; HKEX: 01093), reported promising initial clinical data for SYSA1801 (EO-3021) from the ongoing Phase 1 dose escalation and expansion study in China (Press release, Elevation Oncology, JUN 3, 2023, View Source;utm_medium=rss&utm_campaign=elevation-oncology-highlights-first-in-human-phase-1-sysa1801-eo-3021-clinical-data-to-be-presented-by-partner-cspc-pharmaceutical-group-limited-at-asco-2023 [SID1234632418]). These data will be presented at the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) 2023 Annual Meeting, being held June 2-6, 2023, in Chicago, IL.

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EO-3021 is a potential best-in-class antibody-drug conjugate (ADC) that has been designed to selectively deliver a cytotoxic payload directly to Claudin 18.2-expressing cancer cells to minimize toxicities and maximize anti-tumor activity. EO-3021 is a fully human monoclonal antibody (mAb) that targets Claudin 18.2 and is site-specifically conjugated to the cytotoxic agent monomethyl auristatin E (MMAE), via a cleavable linker with a drug-to-antibody ratio (DAR) of 2. Elevation Oncology’s partner, CSPC, is actively recruiting patients in the Phase 1 clinical trial of SYSA1801 (EO-3021) in China (NCT05009966).

"In these preliminary Phase 1 data, EO-3021 demonstrated an objective response rate of 47% in patients with resistant/refractory gastric cancer expressing Claudin 18.2, with a well-tolerated safety profile in a heavily pretreated patient population," said Valerie Malyvanh Jansen, M.D., Ph.D., Chief Medical Officer of Elevation Oncology. "While the study remains ongoing, the responses seen are particularly impressive, especially in the gastric cancer setting in tumors expressing Claudin 18.2. These results are highly informative as Elevation Oncology prepares to initiate a Phase 1 clinical trial of EO-3021 in the US in the second half of 2023."

"We are highly encouraged by these Phase 1 study data which demonstrate that SYSA1801 (EO-3021) is an active drug that has a well-tolerated safety profile in patients with difficult to treat cancers," said Chunlei Li, Ph.D., Chief Scientific Officer of CSPC Pharmaceutical Group Limited. "These data support the potential of this unique product candidate for patients with Claudin 18.2-expressing cancers."

Key Findings from the Phase 1 Study

As of the data cutoff date of November 5, 2022, 33 patients with resistant/refractory solid tumors that expressed Claudin 18.2 were enrolled
Patients received 0.5 mg/kg to 3 mg/kg of SYSA1801 (EO-3021) administered intravenously (IV) every 3 weeks (Q3W) as part of the dose escalation (n=17) portion of the study; in the dose expansion portion of the study, patients (n=16) were treated at effective doses (2.0 mg/kg IV Q3W and 2.5 mg/kg IV Q3W)
26 patients (78.8%) had gastric cancer (GC); 7 patients (21.2%) had pancreatic cancer
11 patients (33.3%) had been pretreated with ≥3 prior lines of therapy
21 patients (gastric cancer n=17; pancreatic cancer n=4) were evaluable for efficacy per RECIST v1.1
In gastric cancer, the objective response rate (ORR) was 47.1% (8 PRs, including 4 confirmed PRs) and the disease control rate (DCR) was 64.7%, including three patients with stable disease (SD)
The overall ORR was 38.1% (8 PRs, including 4 confirmed PRs) and DCR was 57.1% (including 4 SDs)
Of the 33 patients enrolled at the time of data cutoff, treatment-related adverse events (TRAEs) of any grade occurred in 25 patients (75.8%), including eight (24.2%) TRAEs of ≥Grade 3
The most common TRAEs (occurring in >20% of patients) were nausea (42.4%), vomiting (36.4%), dry eye syndrome (21.2%) and anemia (21.2%)
Two dose-limiting toxicities (DLTs) of Grade 3 nausea and vomiting occurred at the 3 mg/kg IV Q3W dose
No treatment-related deaths were reported
The dose escalation and expansion portion of the study in China is ongoing
Details for the ASCO (Free ASCO Whitepaper) 2023 Presentation are as Follows:

Title: First-in-human dose escalation and expansion study of SYSA1801, an antibody-drug conjugate targeting claudin 18.2 in patients with resistant/refractory solid tumors.
Presenter: Dr. Yakun Wang
Session Type: Poster Discussion Session
Session Title: Molecularly Targeted Agents and Tumor Biology
Poster Session Date and Time: Saturday, June 3, 2023, 8:00 a.m. – 11:00 a.m. CT
Poster Discussion Date and Time: Saturday, June 3, 2023, at 1:15 p.m. CT
Abstract Number: 3016
Poster Number: 214

The full presentation can be accessed under the resources and publications page of the Elevation Oncology website following the completion of the presentation session at ASCO (Free ASCO Whitepaper).

About EO-3021

EO-3021 (also known as SYSA1801) is a differentiated, clinical-stage antibody drug conjugate (ADC) comprised of an immunoglobulin G1 (IgG1) monoclonal antibody (mAb) that targets Claudin 18.2 and is site-specifically conjugated to the monomethyl auristatin E (MMAE) payload via a cleavable linker with a drug-to-antibody ratio (DAR) of 2. Claudin 18.2 is a specific isoform of Claudin 18 that is normally expressed in gastric epithelial cells. During malignant transformation in many solid tumors, the tight junctions may become disrupted, exposing Claudin 18.2 and allowing them to be accessible by Claudin 18.2 targeting agents. An Investigational New Drug application for EO-3021 has been cleared by the U.S. Food and Drug Administration.

On June 3, 2023 Cogent Biosciences, Inc. (Nasdaq: COGT), a biotechnology company focused on developing precision therapies for genetically defined diseases, reported positive lead-in data from its ongoing Phase 3 PEAK trial evaluating the selective KIT D816V inhibitor bezuclastinib in patients with Gastrointestinal Stromal Tumors (GIST) (Press release, Cogent Biosciences, JUN 3, 2023, View Source [SID1234632417]). The data are being presented today in a poster presentation at the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting in Chicago, IL.

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"The results presented today from the lead-in portion of the PEAK study are very encouraging, as the data continue to show that the combination of bezuclastinib and sunitinib has impressive clinical activity in highly refractory GIST patients and is well-tolerated," said Andrew Wagner, M.D., Ph.D., Senior Physician, Center for Sarcoma and Bone Oncology, Dana-Farber Cancer Institute, and Associate Professor of Medicine, Harvard Medical School. "These data reinforce the importance of the ongoing Phase 3 PEAK clinical trial, which has the potential to bring a new standard of care to imatinib-resistant GIST patients."

"These data reinforce our belief that the combination of bezuclastinib and sunitinib has the potential to become a new treatment option for second-line GIST patients," said Andrew Robbins, President, and Chief Executive Officer at Cogent Biosciences. "We are pleased to demonstrate in a robust clinical dataset that the addition of bezuclastinib to sunitinib does not appear to change the frequency or severity of adverse events associated with sunitinib monotherapy. In addition, we are encouraged by the performance of this combination in second-line GIST patients, the population we are currently enrolling in the Phase 3 PEAK clinical trial, with a disease control rate of 100% and 4 out of 7 patients now on treatment for more than 10 cycles."

PEAK Study Design
The PEAK study is a randomized, open-label, global, Phase 3 clinical trial evaluating bezuclastinib in combination with sunitinib in GIST patients previously treated with imatinib. As of the data cutoff date of March 29, 2023, 39 patients had been treated in Part 1, with 19 patients in Part 1a and 20 patients in Part 1b. Seven patients had received only imatinib as prior therapy, and 32 patients had received at least 2 prior tyrosine kinase inhibitor (TKI) therapies.

Safety Data
As of the cutoff date of March 29, 2023, the combination of bezuclastinib and sunitinib was generally well-tolerated with an encouraging safety profile. The majority of treatment-emergent adverse events (TEAEs) were low-grade and reversible, with a low rate of Grade 3 or higher events observed. 23% of patients experienced dose reductions of either medication, and only two patients discontinued treatment due to adverse events. Across Part 1a and Part 1b, there were only two patients with serious adverse events reported that were possibly associated with either study medication including one patient with grade 2 neutrophil count decrease and pyrexia and grade 3 platelet count decrease and one patient with grade 2 bacterial peritonitis and grade 3 febrile neutropenia. Overall, the safety and tolerability profile of the combination appears consistent with that of single-agent sunitinib, suggesting that bezuclastinib is not adding to the overall frequency or severity of adverse events associated with single-agent sunitinib.

Clinical Activity Data
As of the cutoff date, 39 patients had been treated for at least one 28-day cycle, with a range of 1-13 cycles, and 25 of the 39 patients continue to receive treatment. Data were immature to estimate median progression free survival. Across the efficacy evaluable patients in Part 1, the disease control rate (CR + PR + durable SD) is currently 55%; including a 100% disease control rate and 17% ORR among the efficacy evaluable 2nd-line patients in Part 1a. Across the study, 21 patients have demonstrated radiographic evidence of reduction in target lesion diameter, including 4 patients who have achieved partial response. Among those responders the time to first response was as long as 8 cycles, suggesting that patients currently early in treatment may achieve responses over time.

As of June 1, 2023 four of the seven 2nd-line patients in Part 1a remain on study with at least 10 cycles of therapy.

Bezuclastinib Clinical Development
Cogent is actively enrolling patients in Part 2 of the Phase 3 registration-enabling PEAK trial, which is expected to include approximately 388 second-line, post imatinib GIST patients. Additionally, Cogent remains on track to present initial clinical data from SUMMIT, a randomized, double-blind, placebo-controlled, global, multicenter, Phase 2 trial of bezuclastinib in patients with nonadvanced systemic mastocytosis in the second half of 2023. Data will include safety/tolerability, pharmacokinetics, and measures of clinical activity. The Company also expects to present clinical data from approximately 30 patients in Part 1 of the Phase 2 APEX trial in patients with advanced systemic mastocytosis at a scientific meeting in the second half of 2023.

Webcast Information and ASCO (Free ASCO Whitepaper) Poster
Cogent will host a webcast on Monday, June 5, 2023 at 8:00 a.m. ET (7:00 a.m. CT) to discuss today’s update, with participation from Andrew Wagner, M.D., Ph.D., Senior Physician, Center for Sarcoma and Bone Oncology, Dana-Farber Cancer Institute, and Associate Professor of Medicine, Harvard Medical School. The live event can be accessed on the Investor page of Cogent’s website at investors.cogentbio.com. A replay of the webcast will be available approximately two hours after the completion of the event and will be archived for up to 30 days.

The ASCO (Free ASCO Whitepaper) poster is available to registered conference attendees and is also in the Posters and Publications section of Cogent’s website at www.cogentbio.com/research.

On June 3, 2023 Allogene Therapeutics, Inc. (Nasdaq: ALLO), a clinical-stage biotechnology company pioneering the development of allogeneic CAR T (AlloCAR T) products for cancer, reported long-term follow up data from the Phase 1 ALPHA/ALPHA2 trials of ALLO-501/501A in patients with relapsed/refractory (r/r) large B-cell lymphoma (LBCL) at the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting in Chicago, Illinois (Press release, Allogene, JUN 3, 2023, View Source [SID1234632413]). These data will also be presented in a poster session at the European Hematology Association (EHA) (Free EHA Whitepaper) Hybrid Congress on June 9, 2023.

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"We are excited to be the first to demonstrate the potential of allogeneic CD19 CAR T to induce durable complete remissions at a rate similar to approved autologous CD19 CAR T therapies. Our Phase 2 regimen also had a safety profile, including immune recovery, in line with approved options," said Zachary Roberts, M.D., Ph.D., Executive Vice President, Research & Development and Chief Medical Officer. "We believe our AlloCAR T product candidates have the potential to break down widespread access barriers to CAR T, and ultimately establish a new paradigm in cell therapy. These data underlie the excitement we and investigators have for our ongoing potentially pivotal Phase 2 ALPHA2 trial."

The updated analysis of ALPHA/ALPHA2 examined data from 12 CAR T-naïve patients with r/r LBCL who received a single dose of ALLO-501/501A manufactured using the Alloy process following a lymphodepletion regimen (FCA90) comprised of fludarabine (30 mg/m2/day x 3 days) and cyclophosphamide (300 mg/m2/day x 3 days) plus ALLO-647 (30 mg/day x 3 days). The median time from enrollment to the start of therapy was three days and all 12 patients were followed through a minimum of six months (data cutoff April 20, 2023).

Patients Treated with Phase 2 Regimen
(n=12)
Overall Response Rate (ORR), n (%) 8 (67)
Complete Response Rate (CR), n (%) 7 (58)
6 Month Complete Response, n (%) 5 (42)
As of the data cutoff, 7 of 12 (58%) patients achieved a CR and five (42%) maintained a CR through Month 6. Of the five patients who were in CR at 6 months, four (80%) remained in CR. The fifth patient had disease progression at 24 months. The median duration of response was 23.1 months with three patients remaining in remission for over 24 months and the longest remaining in remission for over 31 months.

All r/r CAR T naïve LBCL (N=33) Patients Treated with Phase 2 Regimen (N=12)
All Gr
N (%) Gr 3+
N (%) All Gr
N (%) Gr 3+
N (%)
CRS 8 (24) 0 4 (33) 0
ICANS 0 0 0 0
Neurotoxicity 13 (39) 2 (6) 4 (33) 0
GvHD 0 0 0 0
IRR 16 (49) 3 (9) 8 (67) 0
Infection 19 (58) 5 (15) 8 (67) 1 (8)
Prolonged Gr3+ Cytopenia - 4 (12) - 2 (17)
A safety analysis of 33 CAR T-naïve LBCL patients receiving Alloy process ALLO-501/501A product candidates at any dose and lymphodepletion schedule, including the 12 patients treated with the Phase 2 regimen, was also conducted. Treatment was generally well tolerated with no incidences of Grade 3 or greater cytokine release syndrome, and no cases of immune effector cell-associated neurotoxicity syndrome or graft versus host disease. Cytopenias and infections were manageable and comparable to the experience with autologous CAR T cell therapies in patients with r/r LBCL.

The ALPHA/ALPHA2 Phase 1 trials were designed to assess the safety, tolerability, and preliminary efficacy at increasing dose levels of ALLO-501 and ALLO-501A, allogeneic CAR T cell product candidates that target CD19. In addition to exploring cell doses, these studies evaluated various doses of ALLO-647, Allogene’s proprietary lymphodepleting antibody designed to prevent premature rejection of AlloCAR T cells. Allogene is currently enrolling the potentially pivotal Phase 2 ALPHA2 trial of ALLO-501A in LBCL and expects to complete enrollment in 1H2024.

About ALLO-501 and ALLO-501A
ALLO-501 and ALLO-501A are anti-CD19 AlloCAR T investigational products for the treatment of large B cell lymphoma. ALLO-501A, a next-generation anti-CD19 AlloCAR T, eliminates the rituximab recognition domains in ALLO-501, which could allow for use in a broader patient population, including NHL patients with recent rituximab exposure. This product candidate is currently being studied in an ongoing potentially pivotal Phase 2 trial. In June 2022, the U.S. Food and Drug Administration granted Regenerative Medicine Advanced Therapy (RMAT) designation to ALLO-501A in r/r LBCL.

On June 2, 2023 IGM Biosciences, Inc. (Nasdaq: IGMS), a clinical-stage biotechnology company focused on creating and developing IgM antibodies, reported an update on its clinical development program for IGM-8444, a novel multivalent death receptor 5 (DR5) agonist, in patients with metastatic colorectal cancer (Press release, IGM Biosciences, JUN 2, 2023, View Source [SID1234632823]).

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"We continue to be very pleased with the indications of clinical activity that we are observing with IGM-8444," said Chris Takimoto, M.D., Ph.D., F.A.C.P., Chief Medical Officer of IGM Biosciences. "We are also very pleased with the excellent safety profile that we have seen to date. The absence of clinically significant hepatotoxicity is particularly important, as this has been a challenge for other multivalent DR5 agonists. The long progression-free survival that we have seen in some patients, especially those who have progressed on prior chemotherapy, is quite encouraging as we proceed to further clinical development with FOLFIRI and other combination agents. Our ongoing randomized trial with FOLFIRI plus bevacizumab is designed to confirm and quantify the activity of IGM-8444 in patients with second-line colorectal cancer."

Phase 1 data reported from a cohort of patients treated with IGM-8444 in combination with FOLFIRI, with and without bevacizumab, showed a very encouraging safety profile which was broadly comparable to that expected from chemotherapy alone in this setting. Specifically, in the 51 CRC patients treated with IGM-8444 plus FOLFIRI, with and without bevacizumab, no drug related clinically significant hepatotoxicity was observed and only grade 1 and grade 2 transient liver enzyme elevations were noted, through the data cut-off date of April 12, 2023.

The majority of colorectal patients in this study were on their third-line of treatment or beyond and over 70 percent of the patients treated with the combination regimens had previously been treated with irinotecan-based chemotherapy.

In these predominantly third-line metastatic colorectal cancer patients, the combination of IGM-8444 dosed at 3 mg/kg and FOLFIRI without bevacizumab showed promising activity. This is the group of patients which had the longest treatment follow up. In this 24 patient group, the median progression-free survival (PFS) in the 24 patients was 5.6 months as of the data cut-off date of April 12, 2023, which is higher than the historical median progression-free survival of approximately 2 months with standard of care third-line colorectal cancer treatment without bevacizumab. The longest observed progression-free survival in this group has extended beyond 16 months and 11 of these 24 patients remained on treatment as of the data cut-off. Importantly, multiple patients showed longer durations of treatment with IGM-8444 and FOLFIRI than they had with their previous FOLFIRI regimens.

More recently, the Company began treating patients with the addition of bevacizumab to 3 mg/kg of IGM-8444 and FOLFIRI. For the 17 evaluable patients in this group, the median progression-free survival was not reached and 13 of the 17 patients remained on study, as of the data cut-off.

At the time of the data cut-off, multiple confirmed partial responses were observed among the patients treated with 3 mg/kg of IGM-8444 and FOLFIRI, with and without bevacizumab, including some patients who had previously progressed on FOLFIRI treatment.

Encouraged by these results, IGM has initiated a randomized trial in second-line patients with metastatic colorectal cancer to assess the benefit of 3 mg/kg of IGM-8444 combined with the current standard of care regimen of FOLFIRI and bevacizumab. This open-label trial began in the first quarter of 2023, and the Company hopes to have enrolled approximately 110 patients in the trial by the first quarter of 2024 and to have median progression-free survival data from these patients by the end of 2024.

Conference Call and Webcast

The Company will host a conference call and live webcast to provide an update on its clinical development program for IGM-8444 at 7:00 p.m. ET today, June 2, 2023. The webcast can be accessed by clicking the link: View Source, and will be available on the "Events and Presentations" page in the "Investors" section of the Company’s website. A replay of the webcast will be archived on the Company’s website for 90 days following the presentation. A more detailed presentation of the results will be made available on the Company’s website at www.igmbio.com.

About IGM-8444

IGM-8444 is an IgM antibody targeting death receptor 5 (DR5) that is being developed for the treatment of patients with solid and hematologic malignancies. DR5 is a member of the tumor necrosis factor receptor superfamily (TNFrSF) and is often expressed on the surface of cancer cells. Strong activation of the DR5 pathway requires multiple receptors to be cross-linked simultaneously by an antibody or other binding agent to create an apoptotic death signal to the cell. Unlike traditional IgG antibodies, IGM-8444 has 10 binding units, enabling it to cross-link multiple DR5 receptors at the same time, sending a stronger signal to cause cancer cell death. The Company is currently conducting a multicenter, open-label clinical trial to determine the safety, tolerability, and pharmacokinetics of IGM-8444 as a single agent and in combination in subjects with relapsed and/or refractory solid or hematologic cancers.