BioSpace Report: What Cancer Researchers Are Talking About at AACR 2024

San Diego, Calif. – The American Association for Cancer Research’s annual conference kicks off Friday as more than 20,000 attendees descend on San Diego. Analysts and researchers who spoke with BioSpace said they’re looking forward to early scientific data, and antibody-drug conjugates (ADCs) will be a key focus.

Stay tuned to BioSpace as we keep you updated on all of the biggest data and news from the conference.


Updated: April 8, 3:20 p.m. EST/12:20 p.m. PST

Poseida Therapeutics CAR-T Therapy Shows 60% Response Rate in Multiple Myeloma

Poseida Therapeutics’ lead CAR-T program produced a clinical response in three out of five, or 60%, of multiple myeloma patients, the company announced Monday.

P-BCMA-ALLO1, currently in Phase I clinical trials, is an investigational B-cell maturation antigen (BCMA)-targeted allogeneic CAR-T for patients with relapsed/refractory multiple myeloma that has progressed after BCMA-targeted therapy.

The findings provide additional evidence that the therapy “could be an appropriate treatment for a broader range of patients with multiple myeloma, including those with relapsed/refractory disease whose cancer progressed following prior BCMA-targeted therapy,” Syed Rizvi, M.D., chief medical officer at Poseida, said in a statement. The company is also developing an optimal lymphodepletion regimen for CAR-T in solid tumors, P-MUC1C-ALLO1, Rizvi added.

Poseida plans to deliver more data analysis for both candidates at AACR.


AstraZeneca’s Novel PARP1 Inhibitor Shrinks Tumors in Nearly Half of HRR-Deficient Breast Cancer Patients

A new kind of poly-ADP ribose polymerase 1 (PARP1) inhibitor developed by AstraZeneca assisted in shrinking tumors in 48.4% of people with breast cancers possessing BRCA1/2, PALB2 or RAD51C/D mutations, the company reported Monday at AACR.

In the Phase I/II PETRA trial, funded by AstraZeneca, treatment with 60 mg of saruparib—a selective inhibitor of PARP1—led to an objective response rate was 48.4%, a median duration of response of 7.3 months and a median progression-free survival rate of 9.1 months, according to a news release on the conference’s website.

In a cohort of 141 patients with HRR-deficient breast, ovarian, pancreatic or prostate cancer, adverse events related to saruparib were observed in 76.6% of patients, and 2.1% of patients had a serious adverse event related to the drug.

While blocking PARP1 may be sufficient to prevent DNA repair in HRR-deficient tumors, all FDA-approved PARP inhibitors block both PARP1 and PARP2, which can limit use because of toxicity, Timothy A. Yap, vice president and head of clinical development in the Therapeutics Discovery Division at The University of Texas MD Anderson Cancer Center, said in a statement. “By designing selective PARP1 inhibitors, we have a great opportunity to improve safety, tolerability, pharmacokinetics, pharmacodynamics, efficacy and combinability with other therapies,” Yap said.


BMS Bolsters Recently Accepted Regulatory Application for Krazati/Erbitux Combo with New Data

Bristol Myers Squibb released new data on Monday from a Phase I/II clinical trial of its oral KRAS-inhibitor Krazati (adagrasib) and Eli Lilly’s monoclonal antibody Erbitux (cetuximab) in patients with previously treated KRAS-mutated locally advanced or metastatic colorectal cancer (CRC).

The objective response rate, the primary endpoint for the trial, was 34%, with a median progression-free survival rate of 6.9 months. Median overall survival rate was 15.9 months, while the median duration of response was 5.8 months, BMS reported, with disease control observed in 85% of patients.

The safety profile for the combination was “manageable and consistent” with previous reports and with the recognized safety profile of each drug, according to BMS.

The FDA accepted BMS’s supplemental New Drug Application in this indication in February and set a PDUFA date of June 21, 2024.

“While there has been progress in the treatment of colorectal cancer, there remain groups of patients, such as those with KRAS-mutated cancers, who continue to need new, targeted treatment options,” Anne Kerber, senior vice president, head of late clinical development, hematology, oncology, cell therapy at BMS, said in a statement. “These data highlight the significance of testing and identification of KRASG12C mutations in patients with CRC.”


PDC*line Presents Positive Initial Results for Lung Cancer Vaccine 

European biotech PDC*line Pharma unveiled interim results Monday at AACR from a Phase I/II clinical trial of its vaccine, PDC*lung01, in combination with Keytruda and on its own in non-small cell lung cancer (NSCLC).

Combining a high dose of the vaccine with Keytruda produced an “acceptable safety profile,” PDC*line reported. Most treatment-related adverse events were consistent with those of other injection-based vaccines or with what has already been observed in other cancer vaccine clinical trials, according to the company. No other safety concerns were identified.

The Keytruda and PDC*lung01 combination produced an objective response rate (ORR) of 63.2% and a disease control rate (DCR) of 94.7%. Nine-month progression-free survival (PFS) was recorded at 52.1%, with a median PFS of 10.9 months. The vaccine on its own showed “biological activity” in activating an antitumor immune response in 68.4% of patients. Final analysis of the trial in the third quarter of 2024, PDC*line said.

The company is “encouraged by the evidence of immune response observed in patients, which supports the mechanism of action of PDC*lung01 in relation to clinical activity,” PDC*line Pharma CEO Eric Halioua said in a statement.


Geneos Announces Positive Results for Cancer Vaccine and Keytuda Combination  

Geneos Therapeutics announced Sunday that a Phase I/II trial investigating a combination of its cancer vaccine candidate GNOS-PV02  with PD-1 inhibitor Keytruda and  a DNA plasmid-encoded IL-12 reached the primary endpoints of safety and immunogenicity.

The study, published in Nature Medicine, investigated GNOS-PV02 ’s use as a second-line treatment in patients with advanced hepatocellular carcinoma who have already been treated with a multi-tyrosine kinase inhibitor. Geneos reported a solid safety profile for the candidate, with all adverse events limited to Grades 1 and 2; there were no dose-limiting toxicities or Grade 3 events recorded. The most common adverse events were injection site reactions. The addition of Keytruda in combination with the vaccine did not decrease safety and tolerability, the company noted. As for efficacy, the immunological analysis confirmed the induction of new T cell responses to vaccine-encoded neoantigens in 100% of patients evaluated.

The overall response rate (ORR) was 30.6%, including three complete and eight partial responses, a result Geneos called “statistically significant.”

“To our knowledge, the GT-30 clinical study provides the first definitive demonstration of a personalized cancer vaccine enhancing clinical response to anti-PD-1 therapy by inducing new, neoantigen-specific T cells which traffic to the tumor,” Ildiko Csiki, chief medical officer of Geneos, said in a statement.


Syncromune Debuts Drug-Device Combo in Prostate Cancer 

Florida-based Syncromune presented the first-ever clinical data from SYNC-T, a personalized platform therapy that uses a drug-device combination, in metastatic castration-resistant prostate cancer. Patients in the Phase I study saw an overall response rate (ORR) of 85%—more than double the ORR of 20% to 40% typically seen with standard of care in this patient population, according to the company. There were five complete responses and six partial responses among 13 of 15 evaluable participants, most of whom had bone metastases and had experienced failure with prior therapies. SYNC-T was well-tolerated, with minimal side effects and no significant safety concerns, Syncromune reported.

An in situ therapy, SYNC-T uses a combination of partial tumor lysis and intratumoral immunotherapy. The SYNC-T device activates lysis, which causes tumor cells in the lytic zone to rupture, releasing neoantigens into the tumor microenvironment. Then, SV-102, a fixed-dose multi-target drug, is directly administered into the tumor site to further stimulate the immune system and block mechanisms that suppress the immune response.


Precision’s Antibody Effectively Targets Tregs in Healthy and Cancer Patients

Maryland-based Precision Biologics will present a poster Monday showing that its O-glycan epitope targeting anti-human carcinoma monoclonal antibody candidate, NEO-201, can also target naïve regulatory T cells (Tregs) in both healthy subjects and cancer patients.

The study, which gathered human peripheral blood mononuclear cells (PBMCs) from seven healthy donors and six cancer patients from Precision’s Phase II clinical trial studying NEO-201 in combination with Keytruda in adults with solid tumors, analyzed NEO-201’s ability to recognize naïve Tregs (nTregs) in PBMCs. The analysis showed that NEO-201 recognized fraction I of CD4 T cells in healthy donors, confirming Precision’s earlier findings in PBMCs from cancer patients. The percentage of nTregs in cancer patients was higher than in healthy donors.


Regeneron Touts Durability of Multiple Myeloma Candidate 

Regeneron buttressed its regulatory case for linvoseltamab, an investigational bispecific antibody, with the presentation of positive pivotal data from the Phase I/II LINKER-MM1 trial in relapsed/refractory (R/R) multiple myeloma.

After 11 months of follow-up, treatment with the candidate elicited a 71% objective response rate (ORR), with 46% of patients seeing a complete response or better and 62% achieving a very good partial response or better, Regeneron reported. Median times to reach these metrics were eight months and three months, respectively. After 12 months, the estimated probability of maintaining a response was 78%, progression-free survival was 69% and overall survival was 75%. None of these measures were reached, and Regeneron stated that these data “reinforce [a] high response rate that deepens over time in patients with heavily pre-treated multiple myeloma.”

Linvoseltamab’s safety profile in the Phase I/II LINKER-MM1 trial was less positive, with 85% of patients treated with a 200-mg dose experiencing Grade 3 or worse adverse events (AE), Regeneron reported in December 2023. Fourteen patients—12% of the patient population—died due to treatment-emergent AEs, of which 11 were due to infections.

The FDA in February accepted the Biologics License Application for linvoseltamab in fourth-line R/R multiple myeloma. The candidate is also under review with the European Medicines Agency.


BioNTech/Genentech Cancer Vaccine ‘Persistent’ in Pancreatic Cancer

BioNTech and Genentech’s messenger RNA (mRNA) cancer vaccine candidate, autogene cevumeran, or BNT122/RO7198457, continued to show promise in a particularly difficult-to-treat form of pancreatic cancer three years after treatment, according to an oral presentation Sunday at AACR. Specifically, patients with resected pancreatic ductal adenocarcinoma (PDAC) continued to see polyspecific T-cell responses and delayed tumor recurrence.

Persistence of T cells “was associated with a longer median recurrence-free survival in cancer vaccine responders,” BioNTech reported in a press release. The company called the results an “early signal” of the candidate’s potential in this indication. PDAC carries a 5-year overall survival rate of only 8% to 10%.

Autogene cevumeran, being jointly developed by BioNTech and Genentech, is currently being studied in three ongoing Phase II clinical trials in adjuvant PDAC, first-line melanoma and adjuvant colorectal cancer.


Opdivo Shows Promise in Neoadjuvant Pancreatic Cancer 

Bristol Myers Squibb’s PD-1 inhibitor Opdivo, when combined with several types of chemotherapy prior to surgery, may improve outcomes for pancreatic cancer patients, a pilot study presented at AACR’s annual meeting on Sunday revealed.

The study observed 24 of the 28 trial participants who were given the Opdivo and chemotherapy combination before surgery and had no grade 2 post-operative fistulas. After two years, the combination led to a median progression-free survival rate of 34.8 months; the median overall survival rate was recorded at 35.1 months. No unexpected safety signals were reported, and the addition of Opdivo did not increase the rates of grade three adverse events.

This is the first trial reported of a PD1 inhibitor in neoadjuvant pancreatic cancer, according to the abstract. A Phase II trial is underway.

 

Heather McKenzie is a senior editor at BioSpace. You can reach her at [email protected]. Also follow her on LinkedIn.