Sialic Acid Mediated Endothelial and Hepatic Uptake: A Mechanism based Mathematic Model Elucidating the Complex Pharmacokinetics and Pharmacodynamics of Efmarodocokin Alfa, a Variably Glycosylated Fusion Protein.

Sialic acid (SA) is crucial for protecting glycoproteins from clearance. Efmarodocokin alfa (IL-22Fc), a fusion protein agonist that links IL-22 to the crystallizable fragment (Fc) of human IgG4, contains 8 N-glycosylation sites and exhibits heterogeneous and variable terminal sialylation biodistribution. This presents a unique challenge for Pharmacokinetic (PK) and Pharmacodynamic (PD) analysis and cross-species translation. In this study, we sought to understand how varying SA levels and heterogeneous distribution contribute to IL-22Fc's complex PKPD properties. We initially used homogenous drug material with varying SA levels to examine PKPD in mice. Population PKPD analysis based on mouse data revealed that SA was a critical covariate simultaneously accounting for the substantial between subject variability (BSV) in clearance (CL), distribution clearance (CLd), and volume of distribution (Vd). In addition to the well-established mechanism by which SA inhibits ASGPR activity, we hypothesized a novel mechanism by which decrease in SA increases the drug uptake by endothelial cells. This decrease in SA, leading to more endothelial uptake, was supported by the neonatal Fc receptor (FcRn) dependent cell-based transcytosis assay. The population analysis also suggested in vivo EC50 (IL-22Fc stimulating Reg3ß) was independent on SA, while the in-vitro assay indicated a contradictory finding of SA-in vitro potency relationship. We created a mechanism based mathematical (MBM) PKPD model incorporating the decrease in SA mediated endothelial and hepatic uptake, and successfully characterized the SA influence on IL-22Fc PK, as well as the increased PK exposure being responsible for increased PD. Thereby, the MBM model supported that SA has no direct impact on EC50, aligning with the population PKPD analysis. Subsequently, using the MBM PKPD model, we employed 5 subpopulation simulations to reconstitute the heterogeneity of drug material. The simulation accurately predicted the PKPD of heterogeneously and variably sialylated drug in mouse, monkey and human. The successful prospective validation confirmed the MBM's ability to predict IL-22Fc PK across variable SA levels, homogenous to heterogeneous material, and across species (R2=0.964 for clearance prediction). Our model prediction suggests an average of 1 mol/mol SA increase leads to a 50% increase in drug exposure. This underlines the significance of controlling sialic acid levels during lot-to-lot manufacturing.

Fostering Animal Welfare and Advancing 3Rs Principles through the Establishment of a 3Rs Advisory Group.

Based on the current state of science, the use of animals remains essential in bringing safe and effective medicines to patients. Respect for laboratory animal welfare and the application of 3Rs principles (the replacement, reduction, and refinement of animal use in research) are a priority throughout the pharmaceutical industry. Given the rapid pace of development, technological progress, and the emergence of new-approach methodologies (NAMs) in the field of biomedical research, maintaining a leading position in scientific advancements with a focus on the principles of replace, reduce, and refine (3Rs) can be quite challenging. To effectively address these challenges and sustain a prominent position in the scientific community, organizations can derive significant advantages from establishing an internal 3Rs advisory group (3Rs AG). The primary objective of a 3Rs AG is to stay at the forefront of the knowledge of best practices related to the 3Rs principles in the industry. This group plays a crucial role in fostering innovation and facilitating the seamless integration and implementation of 3Rs principles into a company's policies and procedures. The thoughtful reduction in and replacement of animal studies and the refinement of study designs and practices, enabled by a 3Rs AG, can minimize animal use as well as guide resources and positively impact study and data quality. This article provides guidance on how to establish a successful and impactful 3Rs AG.

The chemical inventory of the inner regions of planet-forming disks - the JWST/MINDS program.

The understanding of planet formation has changed recently, embracing the new idea of pebble accretion. This means that the influx of pebbles from the outer regions of planet-forming disks to their inner zones could determine the composition of planets and their atmospheres. The solid and molecular components delivered to the planet-forming region can be best characterized by mid-infrared spectroscopy. With Spitzer low-resolution (R = 100, 600) spectroscopy, this approach was limited to the detection of abundant molecules, such as H2O, C2H2, HCN and CO2. This contribution will present the first results of the MINDS (MIRI mid-INfrared Disk Survey, PI:Th Henning) project. Due do the sensitivity and spectral resolution provided by the James Webb Space Telescope (JWST), we now have a unique tool to obtain the full inventory of chemistry in the inner disks of solar-type stars and brown dwarfs, including also less-abundant hydrocarbons and isotopologues. The Integral Field Unit (IFU) capabilities will enable at the same time spatial studies of the continuum and line emission in extended sources such as debris disks, the flying saucer and also the search for mid-IR signatures of forming planets in systems such as PDS 70. These JWST observations are complementary to ALMA and NOEMA observations of outer-disk chemistry; together these datasets will provide an integral view of the processes occurring during the planet-formation phase.

Postintensive Care Syndrome: Feasibly Bridging Care at a Tertiary Trauma Center.

BACKGROUND: Advancements in critical care management have improved mortality rates of trauma patients; however, research has identified physical and psychological impairments that remain with patients for an extended time. Cognitive impairments, anxiety, stress, depression, and weakness in the postintensive care phase are an impetus for trauma centers to examine their ability to improve patient outcomes. OBJECTIVE: This article describes one center's efforts to intervene to address postintensive care syndrome in trauma patients. METHODS: This article describes implementing aspects of the Society of Critical Care Medicine's liberation bundle to address postintensive care syndrome in trauma patients. RESULTS: The implementation of the liberation bundle initiatives was successful and well received by trauma staff, patients, and families. It requires strong multidisciplinary commitment and adequate staffing. Continued focus and retraining are requirements in the face of staff turnover and shortages, which are real-world barriers. CONCLUSIONS: Implementation of the liberation bundle was feasible. Although the initiatives were positively received by trauma patients and their families, we identified a gap in the availability of long-term outpatient services for trauma patients after discharge from the hospital.

Economic Benefits from Managing Coffee Berry Borer (Hypothenemus hampei) in Hawaii.

Coffee berry borer (CBB) is considered the most damaging insect pest of coffee worldwide. CBB was first detected on Hawai'i Island in 2010, and quickly spread throughout the state's coffee-growing regions. With the introduction of this pest, Hawaii's small yet economically important coffee industry was changed forever with growers facing significantly higher production and labor costs, as well as decreased yield and coffee quality. We assessed the economic benefits of managing CBB based on three strategies that emerged in Hawaii over the last decade: (1) the use of the entomopathogenic fungus Beauveria bassiana alone, (2) early integrated pest management (IPM), which combined monitoring and sanitation with spraying B. bassiana, and (3) research-based IPM, which focused on CBB biology in Hawaii, optimization of monitoring, B. bassiana applications, and cultural controls. From 2011 to 2021, the economic benefits from managing CBB were USD 52 million using B. bassiana alone, USD 69 million from early IPM, and USD 130 million from research-based IPM, for a total of USD 251 million from all management. Our findings suggest that all types of management provide economic benefits to Hawaii growers, but management strategies based on Hawaii-specific research have provided the greatest gains in coffee yield, price, and revenue.

Navigating Trauma Patients and Families Through Unfamiliar Territory.

BACKGROUND: Trauma teams work diligently to manage the complex medical needs of trauma patients. In addition to medical care, there is also a need to assist patients and their families as they navigate the emotional and physical journey of trauma. The role of trauma nurse navigator was developed to address these holistic needs. OBJECTIVE: This article aims to describe the implementation of a trauma nurse navigator role. METHODS: This article describes the development and implementation of a trauma nurse navigator role at a Level II trauma center in 2018. The trauma nurse navigator serves as a patient resource and utilizes creative problem solving to optimize care. The trauma nurse navigator also serves on the multidisciplinary team, working with providers, nursing staff, rehabilitation staff, and case management to provide seamless care to trauma patients. RESULTS: Implementation of the trauma nurse navigator role was well received by patients, families, and the multidisciplinary trauma team. The trauma nurse navigator role expanded the psychosocial support of trauma patients and increased patient satisfaction. CONCLUSION: Although other specialties have seen the benefits of including a patient navigator on the team, this is a potential for trauma centers as they strive to provide high-quality patient care.

Re-evaluating the need for chronic toxicity studies with therapeutic monoclonal antibodies, using a weight of evidence approach.

To support registration of monoclonal antibodies (mAbs) for chronic indications, 6-month toxicity studies have historically been conducted. Experience with mAb development has shown a relatively benign and well-understood safety profile for this class, with most toxicity findings anticipated based on pharmacology. We evaluated whether a 6-month toxicity study is necessary to assess the long-term safety of mAbs. Data on First-in-Human (FIH)-enabling and chronic toxicity studies were shared for 142 mAbs submitted by 11 companies. Opportunities to further optimize study designs to reduce animal usage were identified. For 71% of mAbs, no toxicities or no new toxicities were noted in chronic studies compared to FIH-enabling study findings. New toxicities of potential concern for human safety or that changed trial design were identified in 13.5% of cases, with 7% being considered critical and 2% leading to program termination. An iterative, weight-of-evidence model which considers factors that influence the overall risk for a mAb to cause toxicity was developed. This model enables an evidence-based justification, suggesting when 3-month toxicity studies are likely sufficient to support late-stage clinical development and registration for some mAbs.

The use of recovery animals in nonclinical safety assessment studies with monoclonal antibodies: further 3Rs opportunities remain.

Assessment of reversibility from nonclinical toxicity findings in animals with potential adverse clinical impact is required during pharmaceutical development, but there is flexibility around how and when this is performed and if recovery animals are necessary. For monoclonal antibodies (mAbs) and in accordance with ICH S6(R1) if inclusion of recovery animals is warranted, this need only occur in one study. Data on study designs for first-in-human (FIH)-enabling and later-development toxicity studies were shared from a recent collaboration between the NC3Rs, EPAA, Netherlands Medicines Evaluation Board (MEB) and 14 pharmaceutical companies. This enabled a review of practices on recovery animal use during mAb development and identification of opportunities to reduce research animal use. Recovery animals were included in 68% of FIH-enabling and 69% of later-development studies, often in multiple studies in the same program. Recovery groups were commonly in control plus one test article-dosed group or in all dose groups (45% of studies, each design). Based on the shared data review and conclusions, limiting inclusion of recovery to a single nonclinical toxicology study and species, study design optimisation and use of existing knowledge instead of additional recovery groups provide opportunities to further reduce animal use within mAb development programs.

Increased risk of infections in pediatric Fontan patients after heart transplantation.

BACKGROUND: Infectious complications are a major cause of morbidity and mortality after HT. Fontan patients may be more susceptible to post-HT infections. METHODS: This was a single-center, retrospective cohort analysis of pediatric patients undergoing HT for FF physiology or DCM, who underwent induction with ATG. The primary endpoint was an infection in the first 180 days post-HT, defined as positive (1) blood/urine/respiratory culture; (2) viral PCR; (3) skin or wound infection; and/or (4) culture-negative infection if ≥5 days of antibiotics were completed. Secondary endpoints included (1) cell counts after ATG; (2) PTLD; and (3) rejection (≥Grade 2R ACR or pAMR2) in the first 180 days post-HT. RESULTS: A total of 59 patients (26 FF, 33 DCM) underwent HT at 14.7 (IQR 10.6, 19.5) and 11.7 (IQR 1.4, 13.6) years of age, respectively. The median total ATG received was 7.4 (IQR 4.9, 7.7) vs 7.5 (IQR 7.3, 7.6) mg/kg (p = NS) for FF and DCM patients, respectively. Twenty-three patients (39%) developed an infection 180 days post-HT, with a higher rate of infection in FF patients (54% vs 27%, p = .03). Adjusted for pre-transplant absolute lymphocyte count, FF patients had a higher risk of infection at 30 days post-HT (OR 7.62, 95% CI 1.13-51.48, p = .04). There was no difference in the incidence of PTLD (12% vs 0%; p = .08) or rejection (12% vs 21%; p = .49). CONCLUSION: Compared to DCM patients, FF patients have a higher risk of infection. Modifications to induction therapy for FF patients should be considered.

Toxicologic Pathology Forum: Opinion on Not Euthanizing Control Animals in the Recovery Phase of Non-Rodent Toxicology Studies.

Nonclinical toxicology studies that are required to support human clinical trials of new drug candidates are generally conducted in a rodent and a non-rodent species. These studies typically contain a vehicle control group and low, intermediate, and high dose test article groups. In addition, a dosing-free recovery phase is sometimes included to determine reversibility of potential toxicities observed during the dosing phase and may include additional animals in the vehicle control and one or more dose groups. Typically, reversibility is determined by comparing the test article-related changes in the dosing phase animals to concurrent recovery phase animals at the same dose level. Therefore, for interpretation of reversibility, it is not always essential to euthanize the recovery vehicle control animals. In the absence of recovery vehicle control tissues, the pathologist's experience, historical control database, digital or glass slide repositories, or literature can be used to interpret the findings in the context of background pathology of the species/strain/age. Therefore, in most studies, the default approach could be not to euthanize recovery vehicle control animals. This article provides opinions on scenarios that may or may not necessitate euthanasia of recovery phase vehicle control animals in nonclinical toxicology studies involving dogs and nonhuman primates.

Enfermedad de Huntington en población panameña, 2007-2021

Introducción: La enfermedad de Huntington (EH) es un desorden neurodegenerativo autosómico dominante caracterizado por disfunción progresiva motora, cognitiva y psiquiátrica1. No se conoce la prevalencia de EH en Centro América (2-11). En Panamá no se han reportado estudios sobre esta Enfermedad. El objetivo es estimar la prevalencia de EH en población panameña. Metodología: Se realizó un estudio descriptivo de casos con EH entre 2007 y 2021 en un hospital de tercer nivel. Se incluyeron individuos panameños, mayores de 15 años, un caso por familia, con cuadro clínico sugestivo, con o sin antecedentes familiares, resonancia magnética cerebral y prueba genética HTT positiva. Estos casos fueron incluidos en el Registro Nacional de Enfermedad de Huntington. Resultados: Presentamos 11 casos índice, 6 femeninos.  Se estima una prevalencia de 0.25 x 100000 habitantes, edad promedio 40 años (rango 23-63), media 43±12.4, la edad de inicio 29 años (rango 14-43), media 27±11.13, presentación juvenil 3 casos. Se detectaron 91 sintomáticos de 185 familiares, transmisión predominante paterna, todos heterocigóticos. Alelo normal entre 13-23 repeticiones de CAG, mientras que alelo mutante oscila entre 41 y 59 repeticiones de CAG. Conclusión: Este es el primer reporte de la EH en población panameña, la prevalencia estimada es baja de 0.25 x 100000 habitantes. Estudios futuros deberán realizarse para conocer la prevalencia en Panamá y Centro América además de determinar el origen ancestral de esta población. (provisto por Infomedic International)

Introduction: Huntington´s disease (HD) is an autosomal dominant neurodegenerative disorder characterized by progressive motor, cognitive and psychiatric dysfunction. HD prevalence in Panama or in Central America is unknown. This will be the first report in Panamá about HD. Metodology: The objective is to estimate HD prevalence in Panamanian population. A retrospective, descriptive study of patients with HD between 2007 and 2021 was conducted. Panamanians > 15 years, 1 case per family, with typical clinical symptoms, with or without family history, brain magnetic resonance and positive genetic test and then included in the National registry of Huntington Disease. Results: Eleven index cases were presented, 6 women. The mean age was 40 years (range 23-63), median 43±12.4, sex ratio was 5:6, the onset age was 29 years (range 14-43), median 27±11.13. 3 cases in young patients. 91 symptomatic cases out of 185 relatives, with a dominant paternal transmission, all heterozygous. Normal allele between 13-23 CAG repetitions, while the mutant allele ranges between 41 and 59 CAG repetitions. Conclusions: This is the first HD report in Panamanian population, with a low estimated prevalence of 0.25 x 100,000. The aim of this study is to promote HD research in Panama and Central America and determine the ancestral origin of this population. (provided by Infomedic International)

Increasing the Reuse of Protein Non-Naïve Nonhuman Primates in Pharmaceutical Drug Discovery and Development: An Overview and Industry Position on the Challenges and Benefits.

The IQ Consortium NHP Reuse Working Group (WG) comprises members from 15 pharmaceutical and biotechnology companies. In 2020, the WG developed and distributed a detailed questionnaire on protein non-naïve NHP reuse to the WG member companies. The WG received responses from key stakeholders including principal investigators, facility managers, animal welfare officers and research scientists. This paper's content reflects the consolidated opinion of the WG members and the questionnaire responses on the subject of NHP reuse within nonclinical programs at all stages of research and development. Many of the pharmaceutical companies represented in the working group or participating in the questionnaire have already achieved some level of NHP reuse in their nonclinical programs, but the survey results suggested that there is significant potential to increase NHP reuse further and a need to understand the considerations involved in reuse more clearly. The WG has also focused carefully on the inherent concerns and risks of implementing protein non-naive NHP reuse and has evaluated the best methods of risk assessment and decision-making. This paper presents a discussion on the challenges and opportunities surrounding protein non-naïve NHP reuse and aims to stimulate further industry dialogue on the subject and provide guidance for pharmaceutical companies to establish roadmaps and decision trees enabling increased protein non-naïve NHP reuse. In addition, this paper represents a solid basis for collaborative engagement between pharmaceutical and biotechnology companies with contract research organizations (CROs) to discuss how the availability of protein non-naïve NHP within CROs can be better leveraged for their use within nonclinical studies.

Variation in Use of High-Flow Nasal Cannula and Noninvasive Ventilation Among Patients With COVID-19.

BACKGROUND: The use of high-flow nasal cannula (HFNC) and noninvasive ventilation (NIV) for hypoxemic respiratory failure secondary to COVID-19 are recommended by critical-care guidelines; however, apprehension about viral particle aerosolization and patient self-inflicted lung injury may have limited use. We aimed to describe hospital variation in the use and clinical outcomes of HFNC and NIV for the management of COVID-19. METHODS: This was a retrospective observational study of adults hospitalized with COVID-19 who received supplemental oxygen between February 15, 2020, and April 12, 2021, across 102 international and United States hospitals by using the COVID-19 Registry. Associations of HFNC and NIV use with clinical outcomes were evaluated by using multivariable adjusted hierarchical random-effects logistic regression models. Hospital variation was characterized by using intraclass correlation and the median odds ratio. RESULTS: Among 13,454 adults with COVID-19 who received supplemental oxygen, 8,143 (60%) received nasal cannula/face mask only, 2,859 (21%) received HFNC, 878 (7%) received NIV, 1,574 (12%) received both HFNC and NIV, with 3,640 subjects (27%) progressing to invasive ventilation. The hospital of admission contributed to 24% of the risk-adjusted variation in HFNC and 30% of the risk-adjusted variation in NIV. The median odds ratio for hospital variation of HFNC was 2.6 (95% CI 1.4-4.9) and of NIV was 3.1 (95% CI 1.2-8.1). Among 5,311 subjects who received HFNC and/or NIV, 2,772 (52%) did not receive invasive ventilation and survived to hospital discharge. Hospital-level use of HFNC or NIV were not associated with the rates of invasive ventilation or mortality. CONCLUSIONS: Hospital variation in the use of HFNC and NIV for acute respiratory failure secondary to COVID-19 was great but was not associated with intubation or mortality. The wide variation and relatively low use of HFNC/NIV observed within our study signaled that implementation of increased HFNC/NIV use in patients with COVID-19 will require changes to current care delivery practices. (ClinicalTrials.gov registration NCT04323787.).

Fatal nocardiosis infection in a pediatric patient with an immunodeficiency after heart re-transplantation.

BACKGROUND: Nocardia infections are rare opportunistic infections in SOT recipients, with few reported pediatric cases. Pediatric patients with single ventricle congenital heart defects requiring HT may be more susceptible to opportunistic infections due to a decreased T-cell repertoire from early thymectomy and potential immunodeficiencies related to their congenital heart disease. Other risk factors in SOT recipients include the use of immunosuppressive medications and the development of persistent lymphopenia, delayed count recovery and/or lymphocyte dysfunction. METHODS: We report the case of a patient with hypoplastic left heart syndrome who underwent neonatal congenital heart surgery (with thymectomy) prior to palliative surgery and 2 HTs. RESULTS: After developing respiratory and neurological symptoms, the patient was found to be positive for Nocardia farcinica by BAL culture and cerebrospinal fluid PCR. Immune cell phenotyping demonstrated an attenuated T and B-cell repertoire. Despite antibiotic and immunoglobulin therapy, his symptoms worsened and he was subsequently discharged with hospice care. CONCLUSION: Pediatric patients with a history of congenital heart defects who undergo neonatal thymectomy prior to heart transplantation and a long-term history of immunosuppression should undergo routine immune system profiling to evaluate for T- and B-cell deficiency as risk factors for opportunistic infection. Such patients could benefit from long-term therapy with TMP/SMX for optimal antimicrobial prophylaxis, with desensitization as needed for allergies. Disseminated nocardiosis should be considered when evaluating acutely ill SOT recipients, especially those with persistent lymphopenia and known or suspected secondary immunodeficiencies.

Targeting the translational machinery in gastrointestinal stromal tumors (GIST): a new therapeutic vulnerability.

Although KIT-mutant GISTs can be effectively treated with tyrosine kinase inhibitors (TKIs), many patients develop resistance to imatinib mesylate (IM) as well as the FDA-approved later-line agents sunitinib, regorafenib and ripretinib. Resistance mechanisms mainly involve secondary mutations in the KIT receptor tyrosine kinase gene indicating continued dependency on the KIT signaling pathway. The fact that the type of secondary mutation confers either sensitivity or resistance towards TKIs and the notion that secondary mutations exhibit intra- and intertumoral heterogeneity complicates the optimal choice of treatment in the imatinib-resistant setting. Therefore, new strategies that target KIT independently of its underlying mutations are urgently needed. Homoharringtonine (HHT) is a first-in-class inhibitor of protein biosynthesis and is FDA-approved for the treatment of chronic myeloid leukemia (CML) that is resistant to at least two TKIs. HHT has also shown activity in KIT-mutant mastocytosis models, which are intrinsically resistant to imatinib and most other TKIs. We hypothesized that HHT could be effective in GIST through downregulation of KIT expression and subsequent decrease of KIT activation and downstream signaling. Testing several GIST cell line models, HHT led to a significant reduction in nascent protein synthesis and was highly effective in the nanomolar range in IM-sensitive and IM-resistant GIST cell lines. HHT treatment resulted in a rapid and complete abolishment of KIT expression and activation, while KIT mRNA levels were minimally affected. The response to HHT involved induction of apoptosis as well as cell cycle arrest. The antitumor activity of HHT was confirmed in a GIST xenograft model. Taken together, inhibition of protein biosynthesis is a promising strategy to overcome TKI resistance in GIST.

Recurrent Croup.

Croup refers to airway inflammation and edema leading to obstruction of the larynx, trachea, and bronchi. Croup is the most common cause of acute airway obstruction in young children. It is characterized by the onset of low-grade fever, barky cough, stridor, hoarseness, and respiratory distress. Croup is typically caused by a viral infection (viral croup) but can occur suddenly without a viral prodrome (spasmodic croup). Recurrent croup is defined as two or more episodes per year. Recurrent croup should be considered a symptom of an underlying structural or inflammatory airway abnormality and should prompt a work-up for the underlying cause.

Pituitary Metastasis Presenting With Central Diabetes Insipidus and Panhypopituitarism.

OBJECTIVE: We report a case of pituitary metastasis (PM) presenting with acute anterior and posterior pituitary dysfunction following a two-decade-long oncologic course marked by disease progression. CASE REPORT: An elderly woman with a history of stage IIA invasive ductal carcinoma of the breast presented with confusion. Her laboratory evaluation was significant for panhypopituitarism and central diabetes insipidus, and magnetic resonance imaging findings were suggestive of PM. She was treated with hormone replacement, resulting in the reversal of her metabolic and cognitive derangements. DISCUSSION: PM is a rare complication of advanced malignancy. Although several malignancies may spread to the pituitary, the most common are breast cancer in women and lung cancer in men. Unlike pituitary adenomas, which predominantly involve the anterior pituitary, PM has a predilection for the posterior lobe and infundibulum due to direct access via systemic circulation. The clinical presentation of PM depends on the size of the metastatic deposit and other structures involved in the vicinity of the sella. Magnetic resonance imaging with gadolinium is the gold standard for the evaluation of sellar masses. The diagnosis of PM involves a thorough history, physical examination, biochemical evaluation of the hypothalamic-pituitary axis, and imaging studies. CONCLUSION: Metastatic involvement of the pituitary is a rare condition seen in <2% of resected pituitary masses. The clinical presentation is heterogeneous and can include headache, visual impairment, and panhypopituitarism. Unfortunately, the presence of PM portends a poor prognosis, and the median survival rate after diagnosis is 6 to 13.6 months.

Multiplexed Quantitative Analysis of Antibody-Drug Conjugates with Labile CBI-Dimer Payloads In Vivo Using Immunoaffinity LC-MS/MS.

Quantitative analysis of antibody-drug conjugates (ADCs) involves cleavage of ADCs into smaller analytes representing different components and subsequent measurements from multiple assays for a more comprehensive pharmacokinetic (PK) assessment. Multiple PK analytes including the drug remaining conjugated to the antibody (or antibody-conjugated drug, acDrug) and total antibody can be accessed simultaneously using a multiplex assay by proteolytic digestion of an ADC, if the sites of conjugation are homogeneous for an ADC and the linker drug is stable to proteases. Herein, a multiplexed immunoaffinity liquid chromatography-mass spectrometry (LC-MS)/MS PK assay is described involving immunoaffinity enrichment, enzymatic conversion of prodrug, trypsin digestion, and LC-MS/MS as applied to next-generation ADCs constructed from linker drugs bearing dimeric cyclopropabenzindole (CBI) payloads (duocarmycin analogues). The cytotoxic payload is chemically labile, requiring extensive optimization in sample preparation steps to stabilize the drug without ex vivo modification and to convert the prodrug into a single active form of the drug. The qualification data for this assay format showed that this approach provides robust acDrug and total antibody data and can be extended to ADCs with different monoclonal antibody frameworks and linker chemistries. Applications of this multiplexed assay to support preclinical studies are presented.

An Anti-CD22-seco-CBI-Dimer Antibody-Drug Conjugate (ADC) for the Treatment of Non-Hodgkin Lymphoma That Provides a Longer Duration of Response than Auristatin-Based ADCs in Preclinical Models.

We are interested in developing a second generation of antibody-drug conjugates (ADCs) for the treatment of non-Hodgkin lymphoma (NHL) that could provide a longer duration of response and be more effective in indolent NHL than the microtubule-inhibiting ADCs pinatuzumab vedotin [anti-CD22-vc-monomethyl auristatin E (MMAE)] and polatuzumab vedotin (anti-CD79b-vc-MMAE). Pinatuzumab vedotin (anti-CD22-vc-MMAE) and polatuzumab vedotin (anti-CD79b-vc-MMAE) are ADCs that contain the microtubule inhibitor MMAE. Clinical trial data suggest that these ADCs have promising efficacy for the treatment of NHL; however, some patients do not respond or become resistant to the ADCs. We tested an anti-CD22 ADC with a seco-CBI-dimer payload, thio-Hu anti-CD22-(LC:K149C)-SN36248, and compared it with pinatuzumab vedotin for its efficacy and duration of response in xenograft models and its ability to deplete normal B cells in cynomolgus monkeys. We found that anti-CD22-(LC:K149C)-SN36248 was effective in xenograft models resistant to pinatuzumab vedotin, gave a longer duration of response, had a different mechanism of resistance, and was able to deplete normal B cells better than pinatuzumab vedotin. These studies provide evidence that anti-CD22-(LC:K149C)-SN36248 has the potential for longer duration of response and more efficacy in indolent NHL than MMAE ADCs and may provide the opportunity to improve outcomes for patients with NHL.