201 BNT221, an autologous neoantigen-specific T-cell product for adoptive cell therapy of metastatic ovarian cancer

BackgroundNeoantigens are tumor-specific antigens that are important in the anti-tumor immune response. These antigens are not subject to central immune tolerance and are therefore potentially more immunogenic than tumor-associated antigens. Here, we present the results of a proof-of-concept, pre-clinical study with multiple successful patient material runs generating a neoantigen-specific T-cell product (BNT221/NEO-PTC-01) using leukaphereses from patients with ovarian cancer. These products contain specific T-cell responses targeting multiple neoantigens from each individual patient‘s tumor.MethodsLeukapheresis and tumor biopsy samples were obtained from multiple patients with ovarian cancer and metastatic melanoma cancer under IRB approval using the N16NEON protocol at the Netherlands Cancer Institute subsidized by BioNTech US. Patient-specific neoantigens from the patient‘s biopsy were predicted using our RECON® bioinformatics platform and the best scoring neoantigens were encoded into synthetic peptides or mRNA molecules and were utilized in our ex vivo stimulation protocol, NEO-STIM®, which is used to prime, activate, and expand memory and de novo T-cell responses from both the CD4+ and the CD8+ compartment. High-throughput flow cytometric analysis was performed to characterize the specificity and functionality (cytokine production and cytolytic capacity) of the induced T-cell responses.ResultsNEO-STIM generates T-cell products specific to neoantigens from the peripheral blood of patients. Data will be presented showing the successful induction of 2–10 CD8+ and 4–13 CD4+ T-cell responses per patient, generated using peripheral blood mononuclear cells from patients with ovarian cancer using our NEO-STIM platform. We extensively characterized these T-cell responses and demonstrate that these responses are polyfunctional, specific and have the capacity to degranulate. T cells in the induced product are of effector memory and central memory phenotypes.ConclusionsNEO-STIM is a novel platform that generates ex vivo T-cell responses to high-quality neoantigen targets. Efforts are ongoing to upscale the manufacturing process and move this into a phase I study. BNT221, the neoantigen-specific T cell product generated from this process, is a potent adoptive cell therapy targeting multiple immunogenic neoantigens in patients with metastatic ovarian cancer.Ethics ApprovalLeukapheresis and tumor biopsy samples were obtained from multiple patients with ovarian cancer and metastatic melanoma cancer under IRB approval using the N16NEON protocol at the Netherlands Cancer Institute subsidized by BioNTech US.

A real or apparent decrease in glomerular filtration rate in patients using olaparib?

Purpose Olaparib is a poly (ADP-ribose) polymerase (PARP) inhibitor indicated for ovarian and metastatic breast cancer. Increased serum creatinine levels have been observed in patients taking olaparib, but the underlying mechanism is unknown. This study aimed to investigate if patients receiving olaparib have increased creatinine levels during olaparib treatment and whether this actually relates to a declined glomerular filtration rate (GFR). Methods We retrospectively identified patients using olaparib at the Netherlands Cancer Institute – Antoni van Leeuwenhoek (NKI-AVL) from 2012 until 2020. Patients with at least one plasma or serum sample available at baseline/off treatment and during olaparib treatment were included. Cystatin C levels were measured, creatinine levels were available and renal function was determined by calculating the estimated glomerular filtration rate (eGFR) using the Creatinine Equation (CKD-EPI 2009) and the Cystatin C Equation (CKD-EPI 2012). Results In total, 66 patients were included. Olaparib treatment was associated with a 14% increase in median creatinine from 72 (inter quartile range (IQR): 22) μmol/L before/off treatment to 82 (IQR: 20) μmol/L during treatment (p < 0.001) and a 13% decrease in median creatinine-derived eGFR from 86 (IQR: 26) mL/min/1.73 m2 before/off treatment to 75 (IQR: 29) mL/min/1.73 m2 during treatment (p < 0.001). Olaparib treatment had no significant effect on median cystatin C levels (p = 0.520) and the median cystatin C–derived eGFR (p = 0.918). Conclusions This study demonstrates that olaparib likely causes inhibition of renal transporters leading to a reversible and dose-dependent increase in creatinine and does not affect GFR, since the median cystatin C–derived eGFR was comparable before/off treatment and during treatment of olaparib. Using the creatinine-derived eGFR can give an underestimation of GFR in patients taking olaparib. Therefore, an alternative renal marker such as cystatin C should be used to accurately calculate eGFR in patients taking olaparib.

Impact of Second Opinions in Breast Cancer Diagnostics and Treatment: A Retrospective Analysis

Background Breast cancer care is becoming increasingly complex, and patients with breast cancer are increasingly aware of the different treatment options, resulting in requests for second opinions (SOs). The current study investigates the impact of breast cancer SOs on final diagnosis and treatment in the Netherlands Cancer Institute (NCI) using a newly designed Breast Cancer Second Opinion (BCSO) classification system. Methods Patients who visited the NCI for an SO between October 2015 and September 2016 were included. Demographics, diagnostics, and treatment proposals were compared between first and SO. Discrepancy was categorized using our BCSO classification system, categorizing SOs into (1) noncomparable, (2) identical, and (3) minor or (4) major discrepancy. Results The majority of SOs (n = 591) were patient initiated (90.7%). A total of 121 patients underwent treatment prior to their SO, leaving 470 patients for assessment of discrepancies according to our BCSO classification system. More than 45% of these SOs resulted in at least one discrepancy, with comparable rates for physician- and patient-initiated SOs (42.5% vs. 45.6%, p = 0.708). Significantly more discrepancies were observed in patients with additional imaging (51.3% vs. 37.2%, p = 0.002) and biopsies (53.7% vs. 40.3%, p = 0.005). Almost 60% of all discrepancies were categorized as major (neoadjuvant systemic treatment instead of primary surgery, breast-conserving surgery instead of mastectomy, and proposing postmastectomy immediate breast reconstruction). Conclusions Our findings show substantial differences in diagnostic and treatment options in breast cancer patients visiting the Netherlands Cancer Institute for an SO, thereby emphasizing more consensus for the indications of these treatment modalities.

Use of leftovers of monoclonal antibody products after partial extraction – A microbiological safety study

Background/purpose In the absence of thorough microbiological, chemical and physical stability data, high amounts of pharmaceutical products, from which the seal has been broken, are to be discarded after preparation. We performed a generic microbiological validation study for several marketed monoclonal antibody products, in order to define conditions under which leftovers from partially extracted product can be used in order to minimize loss. Methods From the daily practice of the Central Preparation Unit of the Netherlands Cancer Institute, used monoclonal antibody product vials were collected. To examine the integrity of the primary packaging, a VDT/S Vacuum Leak tester from Erweka was used. Vials were punctured with different types of spikes or a needle prior to experiments and examined for leakage afterward. In addition, microbiological monitoring was performed by broth simulation of the preparation method. Results All vials (631 vials, 18 different monoclonal antibody products) showed no leakage after puncturing with a 18 G needle. However, the use of a spike system resulted in leakage in 108 of the 435 tested vials. Results from the broth simulations confirmed a higher risk of contamination after puncturing with a spike as compared to needle-punctured vials (0.5% vs. 0.05%). Conclusion When working under aseptic preparation conditions and making use of appropriate needle, the risk of contamination is acceptably low to justify storage and reuse of leftover monoclonal antibody product from a microbiological perspective. The spikes tested lead to an unacceptably high level of loss of integrity and subsequent risk of microbiological contamination if stored in a non-classified environment. We concluded that these results could be applied generically to all monoclonal antibody products with a primary packaging composed of a glass vial and rubber stopper.