Improved mehtods and reagents for pretargeted radioimmunotherapy of cancer

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, February 2007.Vita.Includes bibliographical references.Pretargeted radioimmunotherapy (PRIT) of cancer improves upon conventional radioimmunotherapy (RIT) by decoupling the pharmacokinetics of the targeting agent and the radioisotope. In order to improve upon PRIT, we have considered variables such as treatment setting and methodology, the transport and clearance characteristics of targeting agents, and the radionuclides used for therapy. PRIT has been modeled with the aim of examining the theoretical potential of PRIT under optimal conditions to kill every cell in malignant, avascular micrometastases. A mathematical model of PRIT was developed that combined a two-compartment pharmacokinetic model, antibody binding kinetics, diffusion and catabolism in tumor spheroids, and radiation dosimetry models for alpha- and beta-emitting radionuclides. This model demonstrated that it is theoretically possible to kill every cell in 100 tm radius micrometastases using 9Y- or 213Bi-based PRIT with acceptable toxicity as described. The therapeutic window for dosing radionuclide-carrying hapten was found to be strongly dependent on cell-specific parameters such as antigen concentration, void fraction, and the radiosensitivity parameter a, as well as on targeting agent molecular parameters such as the diffusivity and antigen-binding association rate.(cont.) Surprisingly, the therapeutic window was insensitive to the radiosensitivity metric a/I, the targeting agent antigen-binding dissociation rate, and all pharmacokinetic parameters. Overall, 213Bi-based PRIT significantly outperformed 9Y-based PRIT in terms of the safe therapeutic time window for radiometal dosing and the degree of cell overkill that could be achieved. An attempt was made to isolate high-affinity scFv or linear peptide binders against the loaded metal chelate Ga-DOTA-biotin. Unfortunately, several different approaches led only to scFvs and linear peptides with at best micromolar affinity for Ga-DOTA-biotin. It is possible that Ga-DOTA-biotin is a difficult target against which to engineer high affinity binders due to the chelate's six-coordinate binding of the gallium ion, which may result in rapid exchange of the carboxyl arms of the chelate in solution. As an alternative approach to targeting agent design, an anti-CEA, anti-fluorescein single-chain bispecific diabody was designed, produced in S. cerevisiae and characterized. The full-length diabody (55 kDa) binds CEA expressed on the surface of colorectal cancer-derived SW1222 cells with a KI of 4.3 ± 2.5 nM, and also binds fluorescein while bound to CEA on the cell surface.(cont.) Lastly, in order to assist in protein engineering via directed evolution, asymptotically optimal probability estimation was combined with numerical bootstrapping and non-linear curve fitting to make accurate predictions of the actual underlying diversities of populations based on small samples of data.by Stefan C. Zajic.Ph.D

Bioequivalence of Alendronate and Vitamin D3 in a Combination Tablet Versus Corresponding-Dose Individual Tablets in Healthy Taiwanese Volunteers, Determined Using a Novel Plasma Alendronate Assay

AbstractObjectiveThis study was designed to demonstrate that alendronate (ALN)/vitamin D3 combination tablets (ALN/D5600) are bioequivalent to corresponding doses of ALN and vitamin D3 as individual tablets in healthy Taiwanese volunteers.MethodsIn this open-label, randomized, 2-period, crossover study, 68 volunteers were randomized to a single ALN/D5600 combination tablet or corresponding doses of 70 mg ALN + 5600 IU vitamin D3 (2 × 2800 IU), followed by a 12-day washout period and administration of the alternate formulation. Plasma ALN levels were measured using a newly developed assay. Geometric mean ratios of ALN AUC0–last, AUC0–∞, and Cmax, and unadjusted vitamin D3 AUC0–80h and Cmax were compared and considered bioequivalent if the 90% CI was within 0.8 to 1.25.ResultsThe geometric mean ratios were: AUC0–last, 1.084 (90% CI, 0.937–1.253); AUC0–∞, 1.081 (90% CI, 0.935–1.249); and Cmax, 1.112 (90% CI, 0.959–1.289) for ALN, and AUC0–80h 0.953 (90% CI, 0.827–1.098) and Cmax, 0.982 (90% CI, 0.854–1.130) for vitamin D3 unadjusted for endogenous levels.ConclusionsThe combination tablet was considered bioequivalent to coadministration based on ALN AUC0–∞ and unadjusted vitamin D3 parameters. Slight differences for ALN AUC0–last and Cmax (upper 90% CIs outside the bounds) were not considered clinically significant. The combination tablet was well tolerated. No serious adverse experiences were reported. © 2015. The Authors. Published by Elsevier Inc. All rights reserved

Atlanto-occipital dislocation in a patient presenting with out-of-hospital cardiac arrest: a case report and literature review

Abstract Background Atlanto-occipital dislocation is a rare and severe injury of the upper spine associated with a very poor prognosis. Case presentation We report the case of a 59-year-old European man who suffered from out-of-hospital cardiac arrest following a motor vehicle accident. Cardiopulmonary resuscitation was initiated immediately by bystanders and continued by emergency medical services. After 30 minutes of cardiopulmonary resuscitation with a total of five shocks following initial ventricular fibrillation, return of spontaneous circulation was achieved. An electrocardiogram recorded after return of spontaneous circulation at the scene showed signs of myocardial ischemia as a possible cause for the cardiac arrest. No visible signs of injury were found. He was transferred to the regional academic trauma center. Following an extended diagnostic and therapeutic workup in the emergency room, including extended focused assessment with sonography for trauma ultrasound, whole-body computed tomography, and magnetic resonance imaging (of his head and neck), a diagnosis of major trauma (atlanto-occipital dislocation, bilateral serial rip fractures and pneumothoraces, several severe intracranial bleedings, and other injuries) was made. An unfavorable outcome was initially expected due to suspected tetraplegia and his inability to breathe following atlanto-occipital dislocation. Contrary to initial prognostication, after 22 days of intensive care treatment and four surgical interventions (halo fixation, tracheostomy, intracranial pressure probe, chest drains) he was awake and oriented, spontaneously breathing, and moving his arms and legs. Six weeks after the event he was able to walk without aid. After 2 months of clinical treatment he was able to manage all the activities of daily life on his own. It remains unclear, whether cardiac arrest due to a cardiac cause resulted in complete atony of the paravertebral muscles and caused this extremely severe lesion (atlanto-occipital dislocation) or whether cardiac arrest was caused by apnea due the paraplegia following the spinal injury of the trauma. Conclusions A plausible cause for the trauma was myocardial infarction which led to the car accident and the major trauma in relation to the obviously minor trauma mechanism. With this case report we aim to familiarize clinicians with the mechanism of injury that will assist in the diagnosis of atlanto-occipital dislocation. Furthermore, we seek to emphasize that patients presenting with electrocardiographic signs of myocardial ischemia after high-energy trauma should primarily be transported to a trauma facility in a percutaneous coronary intervention-capable center rather than the catheterization laboratory directly

Bioequivalence of Alendronate and Vitamin D3 in a Combination Tablet Versus Corresponding-Dose Individual Tablets in Healthy Taiwanese Volunteers, Determined Using a Novel Plasma Alendronate Assay

Objective: This study was designed to demonstrate that alendronate (ALN)/vitamin D3 combination tablets (ALN/D5600) are bioequivalent to corresponding doses of ALN and vitamin D3 as individual tablets in healthy Taiwanese volunteers. Methods: In this open-label, randomized, 2-period, crossover study, 68 volunteers were randomized to a single ALN/D5600 combination tablet or corresponding doses of 70 mg ALN + 5600 IU vitamin D3 (2 × 2800 IU), followed by a 12-day washout period and administration of the alternate formulation. Plasma ALN levels were measured using a newly developed assay. Geometric mean ratios of ALN AUC0–last, AUC0–∞, and Cmax, and unadjusted vitamin D3 AUC0–80h and Cmax were compared and considered bioequivalent if the 90% CI was within 0.8 to 1.25. Results: The geometric mean ratios were: AUC0–last, 1.084 (90% CI, 0.937–1.253); AUC0–∞, 1.081 (90% CI, 0.935–1.249); and Cmax, 1.112 (90% CI, 0.959–1.289) for ALN, and AUC0–80h 0.953 (90% CI, 0.827–1.098) and Cmax, 0.982 (90% CI, 0.854–1.130) for vitamin D3 unadjusted for endogenous levels. Conclusions: The combination tablet was considered bioequivalent to coadministration based on ALN AUC0–∞ and unadjusted vitamin D3 parameters. Slight differences for ALN AUC0–last and Cmax (upper 90% CIs outside the bounds) were not considered clinically significant. The combination tablet was well tolerated. No serious adverse experiences were reported. © 2015. The Authors. Published by Elsevier Inc. All rights reserved

Safety and Efficacy of Letetresgene Autoleucel (lete-cel; GSK3377794) Alone or in Combination with Pembrolizumab in Relapsed and Refractory Multiple Myeloma

Abstract Background: Outcomes remain poor for patients with relapsed and refractory multiple myeloma (RRMM) progressing on conventional therapy (proteasome inhibitors, IMiDs, anti-CD38 antibodies, BCMA targeting agents, corticosteroids). Lete-cel, an autologous T-cell therapy, targets NY-ESO-1/LAGE-1a+ tumors using a genetically modified, high-affinity T-cell receptor. NY-ESO-1 and LAGE-1a are immunogenic cancer/testis antigens frequently overexpressed in MM and are linked to poor clinical outcomes. Additionally, PD-1 expression, which may limit adaptive immune response, has been observed previously in RRMM patients following treatment with lete-cel (Stadtmauer et al. Blood Adv, 2019; 3: 2022-2034). This open-label, pilot study evaluated the safety and efficacy of lete-cel +/- pembrolizumab (pembro) in patients with RRMM. Study design and methods: Key eligibility criteria include: age ≥18 yr; HLA-A*02:01; A*02:05, and/or A*02:06; NY-ESO-1+ and/or LAGE-1a+; protocol-required prior regimens; specified washouts from prior therapy; no active/chronic/intercurrent illness. Following lymphodepletion (LD), patients received lete-cel (Arm 1) or lete-cel + pembro (Arm 2). Planned pembro dosing was 200 mg/dose Q3 weeks (wks) starting at Wk 3. Primary endpoint was safety and tolerability. Key efficacy endpoint was investigator-assessed overall response rate (ORR) by International Myeloma Working Group uniform response criteria for MM (2016); response was assessed Q3 wks from Wk 3 to Wk 24, then Q6 wks to Wk 72, then every 3 months (mo) to disease progression/death/withdrawal. NY-ESO-1/LAGE-1a expression was assessed by qRT-PCR on myeloma cells. Transduced cell kinetics were assessed by qPCR of transgene vector copies in DNA from peripheral blood mononuclear cells. Results: Six patients (all male; median age 63 yr) were enrolled; 3 per arm. All had prior systemic anti-cancer therapy; 3 patients had received ≥5 prior regimens. Five of 6 patients received systemic anti-cancer therapy between leukapheresis and LD. All received reduced LD due to age and, in some patients, renal impairment. Patients in each arm received similar numbers of transduced T cells. Each of the 3 patients in Arm 2 received a median of 3 pembro doses (range: 3-4 doses). Start of pembro dosing was delayed to Wk 6 in 2 patients due to ongoing toxicities. There were no Grade 5 AEs. Grade 3/4 T-cell related AEs were reported in 3 patients, and all patients had Grade 3/4 LD-related AEs. Hematopoietic cytopenias were the most common treatment-emergent and treatment-related Grade 3/4 AE, occurring in all patients. All cytopenias were reported to have resolved for 4 patients or to have improved to Grade 1 at final patient follow-up for 2 patients. Three patients had cytokine release syndrome (Arm 1: 1 patient, Grade 2; Arm 2: 2 patients; 1 Grade 1 and 1 Grade 2); all patients recovered. There was 1 event of graft vs host disease (GvHD skin; Grade 1) and, in a separate patient, 1 event of Immune Effector Cell-Associated Neurotoxicity Syndrome (ICANS) (Grade 1). Both events resolved. All patients had reduction in tumor burden. Arm 1 (lete-cel alone) had an ORR of 33.3% (1 CR, 2 SD) and median progression-free survival (PFS) of 2.79 mo, while Arm 2 (combination) had an ORR of 66.7% (1 VGPR, 1 PR, 1 SD) and median PFS of 2.78 mo. Time to response for all responders was 3 weeks. Pembro dosing for the 2 Arm 2 responders began at Wk 6. Duration of response in each responder was 2.1 mo. Overall survival data are not mature. Two of 3 responders exhibited clearance of antigen positive myeloma cells in the bone marrow for up to 6 weeks after lete-cel infusion. T cell kinetics trended toward higher peak expansion (Cmax) and area under the curve (AUC) over the first 28 days post-dose (AUC0-28d) in responders vs. non-responders. Serum cytokine profiles in relation to response and CRS will be discussed. Conclusions: A single lete-cel infusion was associated with antitumor activity in 6/6 heavily pretreated RRMM patients, including 1 CR, 1 VGPR, 1PR. Both responses in Arm 2 occurred prior to pembro initiation. The associated safety profile was manageable and consistent with that seen in other lete-cel studies. Responders showed a trend toward higher Cmax and AUC0-28d as compared to non-responders. The study was closed in November 2020 due to protracted enrollment. This study (208470; NCT03168438) was funded by GlaxoSmithKline. Submission support was provided by Fishawack Health. Disclosures Nishihori: Novartis: Research Funding; Karyopharm: Research Funding. Kaufman: Janssen: Honoraria; Heidelberg Pharma: Research Funding; Fortis Therapeutics: Research Funding; Tecnofarma SAS, AbbVie: Honoraria; Amgen: Research Funding; BMS: Consultancy, Research Funding; Incyte, celgene: Consultancy; Incyte, TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; Genentech, AbbVie, Janssen: Consultancy, Research Funding; Novartis: Research Funding; Roche/Genetech, Tecnopharma: Consultancy, Honoraria; Sutro, Takeda: Research Funding. Huff: GSK: Current Employment, Current equity holder in publicly-traded company. Snape: Veramed: Current Employment. Jain: Butterfly Network: Current equity holder in publicly-traded company; Marker Therapeutics: Current equity holder in publicly-traded company; 23 and Me: Current equity holder in publicly-traded company; Sema4 Holdings: Current equity holder in publicly-traded company; GSK: Current Employment, Current equity holder in publicly-traded company. Kapoor: GSK: Current equity holder in publicly-traded company. Zajic: GSK: Current Employment, Current equity holder in publicly-traded company. Suchindran: GSK: Current Employment, Current equity holder in publicly-traded company. Chisamore: Merck & Co. Inc: Current Employment, Current equity holder in publicly-traded company. Rapoport: GSK: Other: Support received as site principal investigator for this study

Safety and efficacy of letetresgene autoleucel alone or with pembrolizumab for relapsed/refractory multiple myeloma

This pilot study assessed the safety and efficacy of letetresgene autoleucel (lete-cel; GSK3377794), a genetically modified autologous T-cell therapy targeting New York esophageal squamous cell carcinoma-1 (NY-ESO-1)/L antigen family member 1 isoform A (LAGE-1a)-positive myeloma cells, alone or in combination with pembrolizumab in patients with relapsed/refractory multiple myeloma. Eligible patients expressed NY-ESO-1 and/or LAGE-1a and either HLA-A∗02:01, ∗02:05, or ∗02:06. Patients received lete-cel single infusion alone (arm 1) or with pembrolizumab (arm 2). 127 patients were screened, and 6 patients (3 per arm) were enrolled; patients in arm 1 and 2 received lete-cel alone, or with pembrolizumab, respectively. All patients exhibited grade 3/4 cytopenias, which resolved or improved to grade 1. One patient (arm 1) had grade 3/4 lete-cel-related adverse events (AEs); 2 patients (arm 2) had grade 3/4 AEs related to lete-cel and lymphodepletion. Three patients with grade 1/2 cytokine release syndrome (CRS) exhibited elevated post-lete-cel interleukin-6 levels versus those without CRS. Pooled overall response rate was 50% including 1 patient each with confirmed clinical response, very good clinical response, and partial response, and progression-free survival ranged from 1.3 to 5.2 months. Responders (arm 1: n = 1; arm 2: n = 2) had a time-to-response of 3 weeks, duration of response of 2.1 months. Two responders, but no nonresponders, exhibited elevated cytokine levels after lete-cel infusion. Lete-cel had a manageable safety profile and demonstrated clear but transient antitumor activity in patients with relapsed/refractory multiple myeloma. This trial was registered at www.clinicaltrials.gov as #NCT03168438

Exposure-Response Analysis of Dostarlimab in Combination with Platinum-Containing Chemotherapy in Primary Advanced or Recurrent Endometrial Cancer in the ENGOT-EN6-NSGO/GOG-3031/RUBY Trial

peer reviewe

Patient Perceptions and Potential Utility of Pharmacogenetic Testing in Chronic Pain Management and Opioid Use Disorder in the Camden Opioid Research Initiative

Pharmacogenetics (PGx) has the potential to improve opioid medication management. Here, we present patient perception data, pharmacogenetic data and medication management trends in patients with chronic pain (arm 1) and opioid use disorder (arm 2) treated at Cooper University Health Care in Camden City, NJ. Our results demonstrate that the majority of patients in both arms of the study (55% and 65%, respectively) are open to pharmacogenetic testing, and most (66% and 69%, respectively) believe that genetic testing has the potential to improve their medical care. Our results further support the potential for CYP2D6 PGx testing to inform chronic pain medication management for poor metabolizers (PMs) and ultrarapid metabolizers (UMs). Future efforts to implement PGx testing in chronic pain management, however, must address patient concerns about genetic test result access and genetic discrimination