Excessive concentrations of kinase inhibitors in translational studies impede effective drug repurposing.

Drug repositioning seeks to leverage existing clinical knowledge to identify alternative clinical settings for approved drugs. However, repositioning efforts fail to demonstrate improved success rates in late-stage clinical trials. Focusing on 11 approved kinase inhibitors that have been evaluated in 139 repositioning hypotheses, we use data mining to characterize the state of clinical repurposing. Then, using a simple experimental correction with human serum proteins in in vitro pharmacodynamic assays, we develop a measurement of a drug's effective exposure. We show that this metric is remarkably predictive of clinical activity for a panel of five kinase inhibitors across 23 drug variant targets in leukemia. We then validate our model's performance in six other kinase inhibitors for two types of solid tumors: non-small cell lung cancer (NSCLC) and gastrointestinal stromal tumors (GISTs). Our approach presents a straightforward strategy to use existing clinical information and experimental systems to decrease the clinical failure rate in drug repurposing studies.

Discovery of mobocertinib, a potent, oral inhibitor of EGFR exon 20 insertion mutations in non-small cell lung cancer.

In the treatment of non-small cell lung cancer (NSCLC), patients harboring exon 20 insertion mutations in the epidermal growth factor receptor (EGFR) gene (EGFR) have few effective therapies because this subset of mutants is generally resistant to most currently approved EGFR inhibitors. This report describes the structure-guided design of a novel series of potent, irreversible inhibitors of EGFR exon 20 insertion mutations, including the V769_D770insASV and D770_N771insSVD mutants. Extensive structure-activity relationship (SAR) studies led to the discovery of mobocertinib (compound 21c), which inhibited growth of Ba/F3 cells expressing the ASV insertion with a half-maximal inhibitory concentration of 11 nM and with selectivity over wild-type EGFR. Daily oral administration of mobocertinib induced tumor regression in a Ba/F3 ASV xenograft mouse model at well-tolerated doses. Mobocertinib was approved in September 2021 for the treatment of adult patients with advanced NSCLC with EGFR exon 20 insertion mutations with progression on or after platinum-based chemotherapy.

Multiple Sclerosis and Neuromyelitis Optica Spectrum Disorder: Onset Following Acute COVID-19 Infection, a Case Series.

BACKGROUND AND OBJECTIVES: Acute COVID-19 infection has been associated with neurological involvement. We report a case series of newly diagnosed patients with multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) developed in a short period of time after acute COVID-19 infection. METHODS: New MS patients developing initial symptoms shortly after an acute COVID-19 infection were diagnosed based on the 2017 McDonald Criteria [Garcia-Ramos et al. in Cells, 2021]. The patients diagnosed with NMOSD met the 2015 International Panel criteria for the diagnosis of NMOSD (IPDN) [Thompson et al. in Lancet Neurol 17:162-173, 2018]. RESULTS FROM THE MS PATIENT GROUP: Ten patients were included who had developed initial MS symptoms after COVID-19 infection. Gender distribution was equal (50% male). The mean age was 28 (range 17-39) years. Average time to neurological presentation was between 2 and 6 weeks following acute COVID-19 infection. Partial transverse myelitis was the initial presentation in 40% of the cases, and 60% of patients had spinal cord lesions present at the moment of diagnosis. All patients showed enhancing lesions on brain magnetic resonance imaging (MRI). The presence of cerebrospinal fluid (CSF) oligoclonal bands was found in all six tested cases. The majority of patients (80%) were unvaccinated for COVID-19. The two vaccinated patients had received two doses of the monovalent COVID-19 messenger ribonucleic acid (mRNA) (Pfizer Biotech) vaccine and no booster, a year prior to contracting COVID-19. RESULTS FROM THE NMOSD GROUP: Two patients with NMOSD were included. Positive aquoporin-4 protein antibody (AQP-4 Ab) was detected in serum in both cases [one Enzyme Linked immunosorbent assay (ELISA) and one cell based]. Both patients had mild COVID-19 infection prior to presentation, initial neurologic symptoms presented between 3 and 6 weeks after COVID-19 infection. Neither patients were vaccinated. Both responded partially to steroids, one developed a relapse 40 days after diagnosis. CONCLUSION: COVID-19 infection has been linked to several neurological and immune-driven conditions. This study suggests that in susceptible individuals, acute COVID-19 infection may act as a trigger for developing MS and NMOSD.

Neuromyelitis Optica Spectrum Disorder in Central America and the Caribbean: A Multinational Clinical Characterization Study.

Here, a study of NMOSD in Central America and the Caribbean with a multinational collaborative, multicentric and descriptive approach involving 25 institutions from 9 countries is presented. Demographics, clinical manifestations, expanded disability scale status (EDSS), brain and spinal cord MRI, serological anti-AQP4-IgG and anti-MOG-IgG antibodies, and cerebrospinal fluid (CSF) oligoclonal bands were included. A central serological repository utilized the cell-based assay. The specimens outside of this network employed diverse methodologies. Data were collected at the Gorgas Commemorative Institute of Health Studies (ICGES), Panama, and included 186 subjects, of which 84% were females (sex ratio of 5.6:1). Mestizos constituted 72% of the study group. The median age was 42.5 years (IQR: 32.0-52.0). Associated autoimmune diseases (8.1%) were myasthenia gravis, Sjögren's syndrome and systemic lupus erythematosus. The most common manifestation was optic neuritis-transverse myelitis (42.5%). A relapsing course was described in 72.3% of cases. EDSS scores of 0-3.5 were reported in 57.2% of cases and higher than 7.0 in 14.5%. Positive anti-AQP4-IgG antibody occurred in 59.8% and anti-MOG-IgG antibody in 11.5% of individuals. Antibody testing was lacking for 13.4% of patients. The estimated crude prevalence of NMOSD from Panama and the Dominican Republic was 1.62/100,000 (incidence of 0.08-0.41) and 0.73/100,000 (incidence 0.02-0.14), respectively. This multinational study contributes additional insights and data on the understanding of NMOSD in this Latin American region.

Phase II Study of Ponatinib in Advanced Gastrointestinal Stromal Tumors: Efficacy, Safety, and Impact of Liquid Biopsy and Other Biomarkers.

PURPOSE: The purpose of this study is to evaluate ponatinib for advanced gastrointestinal stromal tumors (GIST). PATIENTS AND METHODS: This single-arm phase II trial enrolled patients with metastatic and/or unresectable GIST with failure of prior tyrosine kinase inhibitor (TKI) treatment into two cohorts based on presence or absence of KIT exon 11 (ex11) primary mutations. Patients initially received ponatinib 45 mg once daily. Following a temporary clinical hold in October 2013, dose reductions were implemented to reduce risk of arterial occlusive events (AOE). Primary endpoint was 16-week clinical benefit rate (CBR) in KIT ex11-positive cohort. KIT mutations in circulating tumor DNA (ctDNA) were assessed. RESULTS: Forty-five patients enrolled (30 KIT ex11-positive and 15 KIT ex11-negative); median follow-up was 14.7 and 13.6 months, respectively, as of August 1, 2016. Sixteen-week CBR was 36% (KIT ex11-positive; primary endpoint) and 20% (KIT ex11-negative). ctDNA analyses (n = 37) demonstrated strong concordance of primary KIT mutations between plasma and tumor. At least two secondary mutations were detected in 35% of patients overall and 54% of KIT ex11-positive patients. Changes from baseline in mutated ctDNA levels were consistent with clinical activity. Ponatinib was ineffective in patients with KIT exon 9 primary mutations. Resistance was associated with emergence of V654A. AOEs and venous thromboembolic events occurred in three and two patients, respectively. Six patients died; two deaths (pneumonia and pulmonary embolism) were considered possibly ponatinib-related. CONCLUSIONS: Ponatinib demonstrated activity in advanced GIST, particularly in KIT ex11-positive disease. ctDNA analysis confirmed heterogeneous resistance mutations in TKI-pretreated advanced GIST. Safety was consistent with previous studies.

Editorial of Special Issue "Multiple Sclerosis: Diagnosis and Treatment II".

The special issue on Multiple Sclerosis: Diagnosis and Treatment II, reflects advances and discoveries in the molecular and cellular mechanisms of disease, and novel laboratory techniques providing more sensitivity to diagnostic techninques and the understanding of neuroinflammation. Mitochondrial-mediated apoptosis in isolated peripheral blood mononuclear cells and the role of reactive oxygen species are studied as indicators of activity of MS. In these cells, downregulation of circular and linera RNAs are reported as markers of highly active disease in MS. Progress and importance of Neurofilaments determinations in early diagnosis and as a marker of disease activity, and the analysis of the complex mechanisms and therapeutic potential of Sphingosine-1-phosphate receptor modulator are discussed. Epidemiologic observations from a highly diversified area of the world provide more insights into this important aspect of MS; discussions on the clinical challenges posed by spinal cord involvement in demyelinatind disorders and the latest aspects of pediatric onset MS, complement this fine collection of scientific papers.

Health Disparities, Inequities, and Social Determinants of Health in Multiple Sclerosis and Related Disorders in the US: A Review.

Importance: There is empirical evidence that social determinants of health (SDOH) impact health outcomes in Black and Hispanic and Latinx individuals in the US. Recently, SDOH have risen to the top as essential intervention targets that could help alleviate racial and ethnic disparities. Neuromyelitis optica spectrum disorder (NMOSD) disproportionately affects Black individuals, and multiple sclerosis (MS) has seen a recent shift in select racial groups. It is unclear to what degree SDOH have been investigated and contribute to racial and ethnic health disparities and inequities. Observations: This narrative review provides a contemporary synthesis of SDOH associated with racial and ethnic health disparities and inequities in MS, NMOSD, and other autoimmune disorders, such as myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated disease. These immune-mediated neurological diseases were chosen for their capacity to be a high burden to society and because of complementary SDOH-associated challenges among minority populations. A paucity of research addressing inequities and the role of SDOH in MS and NMOSD was noted despite findings that Black individuals have a higher risk of developing MS or NMOSD and associated mortality compared with White individuals. Greater health disparities were also found for those with lower income and education, lower health literacy, and negative illness perceptions in MS. No studies in MOG-Ab disorders were found. Conclusions and Relevance: Increased efforts are needed to better understand the role of SDOH in racial and ethnic health disparities and inequities in MS, NMOSD, and emerging autoimmune disorders. This includes developing research frameworks aimed at understanding the magnitude and interrelationships of SDOH to better develop system-based multilevel interventions across the spectrum of care for these neurological conditions.

Targeting HER2 Exon 20 Insertion-Mutant Lung Adenocarcinoma with a Novel Tyrosine Kinase Inhibitor Mobocertinib.

No targeted treatments are currently approved for HER2 exon 20 insertion-mutant lung adenocarcinoma patients. Mobocertinib (TAK-788) is a potent irreversible tyrosine kinase inhibitor (TKI) designed to target human epidermal growth factor receptor 2 (HER2/ERBB2) exon 20 insertion mutations. However, the function of mobocertinib on HER2 exon 20 insertion-mutant lung cancer is still unclear. Here we conducted systematic characterization of preclinical models to understand the activity profile of mobocertinib against HER2 exon 20 insertions. In HER2 exon 20 insertion-mutant cell lines, the IC50 of mobocertinib was higher than poziotinib and comparable with or slightly lower than afatinib, neratinib, and pyrotinib. Mobocertinib had the lowest HER2 exon 20 insertion IC50/wild-type (WT) EGFR IC50 ratio, indicating that mobocertinib displayed the best selectivity profile in these models. Also, mobocertinib showed strong inhibitory activity in HER2 exon 20YVMA allograft and patient-derived xenograft models. In genetically engineered mouse models, HER2 exon 20G776>VC lung tumors exhibited a sustained complete response to mobocertinib, whereas HER2 exon 20YVMA tumors showed only partial and transient response. Combined treatment with a second antibody-drug conjugate (ADC) against HER2, ado-trastuzumab emtansine (T-DM1), synergized with mobocertinib in HER2 exon 20YVMA tumors. In addition to the tumor cell autonomous effect, sustained tumor growth control derived from M1 macrophage infiltration and CD4+ T-cell activation. These findings support the ongoing clinical development of mobocertinib (NCT02716116) and provide a rationale for future clinical evaluation of T-DM1 combinational therapy in HER2 exon 20YVMA insertion-mutant lung adenocarcinoma patients. SIGNIFICANCE: This study elucidates the potent inhibitory activity of mobocertinib against HER2 exon 20 insertion-mutant lung cancer and the synergic effect of combined mobocertinib and T-DM1, providing a strong rationale for clinical investigation.

Status of the neuromyelitis optica spectrum disorder in Latin America.

BACKGROUND: Neuromyelitis optica spectrum disorders (NMOSD) is an increasing diagnostic and therapeutic challenge in Latin America (LATAM). Despite the heterogeneity of this population, ethnic and socioeconomic commonalities exist, and epidemiologic studies from the region have had a limited geographic and population outreach. Identification of some aspects from the entire region are lacking. OBJECTIVES: To determine ethnic, clinical characteristics, and utilization of diagnostic tools and types of therapy for patients with NMOSD in the entire Latin American region. METHODS: The Latin American Committee for Treatment and Research in MS (LACTRIMS) created an exploratory investigational survey addressed by Invitation to NMOSD Latin American experts identified through diverse sources. Data input closed after 30 days from the initial invitation. The questionnaire allowed use of absolute numbers or percentages. Multiple option responses covering 25 themes included definition of type of practice; number of NMOSD cases; ethnicity; utilization of the 2015 International Panel criteria for the diagnosis of Neuromyelitis optica (IPDN); clinical phenotypes; methodology utilized for determination of anti-Aquaporin-4 (anti- AQP4) antibodies serological testing, and if this was performed locally or processed abroad; treatment of relapses, and long-term management were surveyed. RESULTS: We identified 62 investigators from 21 countries reporting information from 2154 patients (utilizing the IPDN criteria in 93.9% of cases), which were categorized in two geographical regions: North-Central, including the Caribbean (NCC), and South America (SA). Ethnic identification disclosed Mestizos 61.4% as the main group. The most common presenting symptoms were concomitant presence of optic neuritis and transverse myelitis in 31.8% (p=0.95); only optic neuritis in 31.4% (more common in SA), p<0.001); involvement of the area postrema occurred in 21.5% and brain stem in 8.3%, both were more frequent in the South American cases (p<0.001). Anti-AQP4 antibodies were positive in 63.9% and anti-Myelin Oligodendrocyte Glycoprotein (MOG) antibodies in 4.8% of total cases. The specific laboratorial method employed was not known by 23.8% of the investigators. Acute relapses were identified in 81.6% of cases, and were treated in 93.9% of them with intravenous steroids (IVS); 62.1% with plasma exchange (PE), and 40.9% with intravenous immunoglobulin-G (IVIG). Therapy was escalated in some cases due to suboptimal initial response. Respondents favored Rituximab as long-term therapy (86.3%), whereas azathioprine was also utilized on 81.8% of the cases, either agent used indistinctly by the investigators according to treatment accessibility or clinical judgement. There were no differences among the geographic regions. CONCLUSIONS: This is the first study including all countries of LATAM and the largest cohort reported from a multinational specific world area. Ethnic distributions and phenotypic features of the disease in the region, challenges in access to diagnostic tools and therapy were identified. The Latin American neurological community should play a determinant role encouraging and advising local institutions and health officials in the availability of more sensitive and modern diagnostic methodology, in facilitating the the access to licensed medications for NMOSD, and addressing concerns on education, diagnosis and management of the disease in the community.

Research priorities in multiple sclerosis in Latin America: A multi-stakeholder call to action to improve patients care: Research priorities in MS in LATAM.

As human and economic resources are limited, especially in Latin America (LATAM), it is important to identify research priorities to improve multiple sclerosis (MS) patients care in the region. The objective was to generate a multidisciplinary consensus on research priorities in MS for patients care in LATAM by involving healthcare professionals and MS patient associations. METHODS: consensus was reached through a four-step modified Delphi method designed to identify and rate research priorities in MS in LATAM. The process consisted of two qualitative assessments, a general ranking phase and a consensus meeting followed by a more detailed ranking phase RESULTS: a total of 62 participants (35 neurologists, 4 nurses, 12 kinesiologists, 7 neuropsychologists and 4 patient association members) developed the process. At the final ranking stage following the consensus meeting, each participant provided their final rankings, and the top priority research questions were outlined. 11 research priorities were identified focusing on healthcare access, costs of the disease, physical and cognitive evaluation and rehabilitation, quality of life, symptoms management, prognostic factors, the need of MS care units and patient's management in emergencies like COVID-19. CONCLUSION: this work establishes MS research priorities in LATAM from multiple perspectives. To pursue the actions suggested could launch the drive to obtain information that will help us to better understand the disease in our region and, especially, to better care for affected patients.

Mobocertinib (TAK-788): A Targeted Inhibitor of EGFR Exon 20 Insertion Mutants in Non-Small Cell Lung Cancer.

Most EGFR exon 20 insertion (EGFRex20ins) driver mutations in non-small cell lung cancer (NSCLC) are insensitive to approved EGFR tyrosine kinase inhibitors (TKI). To address the limitations of existing therapies targeting EGFR-mutated NSCLC, mobocertinib (TAK-788), a novel irreversible EGFR TKI, was specifically designed to potently inhibit oncogenic variants containing activating EGFRex20ins mutations with selectivity over wild-type EGFR. The in vitro and in vivo activity of mobocertinib was evaluated in engineered and patient-derived models harboring diverse EGFRex20ins mutations. Mobocertinib inhibited viability of various EGFRex20ins-driven cell lines more potently than approved EGFR TKIs and demonstrated in vivo antitumor efficacy in patient-derived xenografts and murine orthotopic models. These findings support the ongoing clinical development of mobocertinib for the treatment of EGFRex20ins-mutated NSCLC. SIGNIFICANCE: No oral EGFR-targeted therapies are approved for EGFR exon 20 insertion (EGFRex20ins) mutation-driven NSCLC. Mobocertinib is a novel small-molecule EGFR inhibitor specifically designed to target EGFRex20ins mutants. Preclinical data reported here support the clinical development of mobocertinib in patients with NSCLC with EGFR exon 20 insertion mutations.See related commentary by Pacheco, p. 1617.This article is highlighted in the In This Issue feature, p. 1601.

Ultra-accurate Duplex Sequencing for the assessment of pretreatment ABL1 kinase domain mutations in Ph+ ALL.

Mutations of ABL1 are the dominant mechanism of relapse in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL). We performed highly accurate Duplex Sequencing of exons 4-10 of ABL1 on bone marrow or peripheral blood samples from 63 adult patients with previously untreated Ph + ALL who received induction with intensive chemotherapy plus a BCR-ABL1 TKI. We identified ABL1 mutations prior to BCR-ABL1 TKI exposure in 78% of patients. However, these mutations were generally present at extremely low levels (median variant allelic frequency 0.008% [range, 0.004%-3.71%] and did not clonally expand and lead to relapse in any patient, even when the pretreatment mutation was known to confer resistance to the TKI received. In relapse samples harboring a TKI-resistant ABL1 mutation, the corresponding mutation could not be detected pretreatment, despite validated sequencing sensitivity of Duplex Sequencing down to 0.005%. In samples under the selective pressure of ongoing TKI therapy, we detected low-level, emerging resistance mutations up to 5 months prior to relapse. These findings suggest that pretreatment ABL1 mutation assessment should not guide upfront TKI selection in Ph + ALL, although serial testing while on TKI therapy may allow for early detection of clinically actionable resistant clones.

Current Advances in Pediatric Onset Multiple Sclerosis.

Multiple sclerosis (MS) is an autoimmune inflammatory disease affecting the central nervous system leading to demyelination. MS in the pediatric population is rare, but has been shown to lead to significant disability over the duration of the disease. As we have learned more about pediatric MS, there has been a development of improved diagnostic criteria leading to earlier diagnosis, earlier initiation of disease-modifying therapies (DMT), and an increasing number of DMT used in the treatment of pediatric MS. Over time, treatment with DMT has trended towards the initiation of higher efficacy treatment at time of diagnosis to help prevent further disease progression and accrual of disability over time, and there is evidence in current literature that supports this change in treatment patterns. In this review, we discuss the current knowledge in diagnosis, treatment, and clinical outcomes in pediatric MS.

Biosimilar Drugs for Multiple Sclerosis: An Unmet International Need or a Regulatory Risk?

Multiple sclerosis (MS) more than any other neurological disorder has experienced a tremendous progress in available evidence-based innovator disease modifying therapies (DMT). These medications include injectable complex nonbiological drugs (CNBD), the injectable biological products ß-interferons-1a and -1b, and the infusible monoclonal antibodies (MAB), as well as oral synthetic therapeutic molecules. The degree of efficacy and adverse effects profile is variable. By the end of 2019, all medications have been approved for relapsing forms of MS, including five with indication for clinically isolated syndrome (CIS), two for active secondary progressive MS, and one for primary progressive MS. With the advent of the first generation or "platform" injectable DMT in the 1990s the cost of MS care increased substantially driven basically by the cost of these therapies. As new drugs licensed by health agencies appeared in the global market, the cost of these agents notably increased augmenting the economic gravamen of disease particularly in North America This industrial phenomenon has been promoted by the remarkable profits obtained by the biopharmaceutical companies producing these medications, costs increasing about seven times per patient per year in the span of two decades. The global MS drug market was valued at US$16.3 billion in 2016, expecting to reach US$27.8 billion by 2025. The societal and economic effect of these costs constitute an international concern for health systems which adjudicate an increasing portion of financial resources to MS care. This effect has had a more notorious impact in emerging countries with economies in development. In the early 2000s the industry producers of biosimilar molecules initiated the concept of manufacturing follow-on biosimilar therapeutic options for MS available at a reduced cost without affecting efficacy and safety. Latin American biotechnological companies from Mexico, Argentina and Uruguay, introduced into the regional markets biosimilar ß-interferons. These products were licensed by the local regulatory agencies without challenging pharmacological profile and their claims of similarity with the innovator medications. In the licensing process, biosimilar manufactures have typically utilized published literature and phase III clinical trials data previously acquired by the brand medication ("third approval pathway''). This has raised concerns among local neurological communities and patient organizations in the area. This situation is compounded by the fact that no discernible health cost savings have resulted since their introduction in Latin American countries. In some European countries where the health care system, public and private systems, regulated by Ministries of Health, negotiate with the pharmaceutical industry drug pricing and payment systems. The business scenario has stimulated local industries to produce follow-on biosimilar medications, theoretically to compete or replace the original brands. Countries such as Iran who have experienced a substantial increase in MS prevalence (101.19 per 100,000 inhabitants) has enabled their national Food and Drug Organization (FDO) to license locally produced biosimilar interferon 1-a and 1-b based on somewhat limited clinical studies. The Ministry of Health of the Russian Federation, approved the first biosimilar ß-interferon-1a (44 mcg subcutaneous administration) manufactured in the country and developed in accordance to the guidelines of the European Medicine Agency (EMA) for phase I and phase III studies. The EMA, however, along with other international licensing agencies: United States Food and Drug Agency (FDA), Health Canada, the Japanese Pharmaceuticals and Medical Devices Agency (PMDA), the UK Medicines and Healthcare Products Regulatory Agency (MHPRA), and others, have produced strict guidelines regulating registration of biosimilar medicines. Thus far these agencies have not approved any interferon or MAB for MS based on these principles. The main obstacles for the approval of biosimilar medications by international health agencies is their consistent inability to demonstrate therapeutic equivalence through physiochemistry, biology, immunogenicity aspects, molecular behavior and clinical studies, preferably through a controlled phase III study, or ideally, utilizing a comparative head-to-head trial with the innovator. Recommendations proposed by experts from the Latin American region to guarantee production quality of biosimilar products, efficacy and safety, include strict application of current regulations; avoid uncontrolled interchangeability; implement strong pharmacovigilance; educate healthcare professionals and regulatory officials on the different issues involved in the biosimilarity concept and use evidence-based decision for therapy selection. The main priority should always be the protection and well-being of the patient irrespectively of therapy availability or pharmacoeconomic issues.

Experimental design of a simple medium for the bioluminescence of Aliivibrio fischeri and mathematical modelling for growth estimation.

Increasing numbers of studies are using Aliivibrio fischeri (A. fischeri), a marine bioluminescent bacterium as a model, however the culture medium used for its growth are complex and expensive. The objectives of this study were: (1) to evaluate the effect of yeast extract, tryptone, and NaCl to select a simple and inexpensive culture medium suitable for A. fischeri growth and bioluminescence induction; and (2) to compare the performance of mathematical models to predict the growth of A. fischeri. A fractional factorial design was performed to evaluate the effect of yeast extract, tryptone, and sodium chloride on the luminescence of A. fischeri. The result showed that sodium chloride is the most important factor, congruent with its inducer role in bioluminescence. The best medium for bioluminescence induction was selected through an optimization plot, this medium is inexpensive, and generates the same luminescence as commercial formulations. The estimation of A. fischeri growth at OD600 measurement was statistically analyzed. All evaluated models fitted the data adequately (r2  > 0.96). The nonlinear models Gompertz, Richards and logistic provided a lower variation and a better fit of the growth estimation (r2 >0.99), showing that these mathematical models can be used for the accurate growth prediction of A. fischeri.

Multiple Sclerosis: A Global Concern with Multiple Challenges in an Era of Advanced Therapeutic Complex Molecules and Biological Medicines.

Multiple sclerosis (MS) has become a common neurological disorder involving populations previously considered to be infrequently affected. Genetic dissemination from high- to low-risk groups is a determining influence interacting with environmental and epigenetic factors, mostly unidentified. Disease modifying therapies (DMT) are effective in treating relapsing MS in variable degrees; one agent is approved for primary progressive disease, and several are in development. In the era of high-efficacy medications, complex molecules, and monoclonal antibodies (MAB), including anti-VLA4 (natalizumab), anti-CD52 (alemtuzumab), and anti-CD20 (ocrelizumab), obtaining NEDA (no evidence of disease activity) becomes an elusive accomplishment in areas of the world where access to MS therapies and care are generally limited. Countries' income and access to public MS care appear to be a shared socioeconomic challenge. This disparity is also notable in the utilization of diagnostic tools to adhere to the proposed elements of the McDonald Criteria. The impact of follow-on medications ("generics"); injectable non-biological complex drugs (NBCD), oral sphingosine-1-phosphate receptor modulators, and biosimilars (interferon 1-a and 1-b), utilized in many areas of the world, is disconcerting considering these products generally lack data documenting their efficacy and safety. Potential strategies addressing these concerns are discussed from an international point of view.

RET fusions observed in lung and colorectal cancers are sensitive to ponatinib.

Genomic studies are revolutionizing clinical oncology, but bridging the lab and the bedside requires the ability to efficiently interrogate rare genetic lesions in unexpected pathological settings using preclinical models. Oncogenes can exhibit intrinsic drug resistance to targeted therapy in different cells of origin, adding complexity to clinical interpretations of genomic findings. Here, we capitalize on the flexibility of engineered cell systems to rapidly profile known multi-kinase inhibitors that harbor rearranged during transfection (RET) kinase activity across multiple RET fusions. Identifying ponatinib as the most potent RET inhibitor tested, we used ponatinib to gauge therapeutic responsiveness in RET fusion-positive patient-derived xenograft (PDX) models. Using a genomics guided outlier approach, we identified 4 RET fusion PDX models with 3 different fusion partners (KIF5B, CCDC6, and NCOA4) in both non-small cell lung cancer and colorectal cancer. By comparing ponatinib activity in RET fusion-positive and RET fusion-negative PDX models alongside a standard of care chemotherapeutic agent, we show that RET fusions in colorectal tumors are therapeutically responsive to RET inhibition. Finally, we suggest that coupling engineered cell systems and genomics guided PDX model selection provides a rapid workflow to triage rare genomics findings.

Single-Molecule Sequencing Reveals Patterns of Preexisting Drug Resistance That Suggest Treatment Strategies in Philadelphia-Positive Leukemias.

Purpose: Sequential treatment with targeted therapies can result in complex combinations of resistance mutations in drug targets. This mutational complexity has spurred the development of pan-target inhibitors, i.e., therapies for which no single target mutation can cause resistance. Because the propensity for on- versus off-target resistance varies across cancer types, a deeper understanding of the mutational burden in drug targets could rationalize treatment outcomes and prioritize pan-target inhibitors for indications where on-target mutations are most likely.Experimental Design: To measure and model the mutational landscape of a drug target at high resolution, we integrated single-molecule Duplex Sequencing of the ABL1 gene in Philadelphia-positive (Ph+) leukemias with computational simulations.Results: A combination of drug target mutational burden and tumor-initiating cell fraction is sufficient to predict that most patients with chronic myeloid leukemia are unlikely to harbor ABL1 resistance mutations at the time of diagnosis, rationalizing the exceptional success of targeted therapy in this setting. In contrast, our analysis predicts that many patients with Ph+ acute lymphoblastic leukemia (Ph+ ALL) harbor multiple preexisting resistant cells with single mutants. The emergence of compound mutations can be traced to initial use of an ABL1 inhibitor that is susceptible to resistance from single point mutations.Conclusions: These results argue that early use of therapies that achieve pan-inhibition of ABL1 resistance mutants might improve outcomes in Ph+ ALL. Our findings show how a deep understanding of the mutational burden in drug targets can be quantitatively coupled to phenotypic heterogeneity to rationalize clinical phenomena. Clin Cancer Res; 24(21); 5321-34. ©2018 AACR.