Impact of Prior Tuberculosis Treatment With New/Companion Drugs on Clinical Outcomes in Patients Receiving Concomitant Bedaquiline and Delamanid for Multidrug- and Rifampicin-Resistant Tuberculosis

BACKGROUND

There are scarce data on the clinical outcomes of persons retreated with new/companion anti-tuberculosis (TB) drugs for multidrug- and rifampicin-resistant tuberculosis (MDR/RR-TB). We sought to evaluate the efficacy and safety of bedaquiline and delamanid containing regimens among patients with and without prior exposure to the new/companion drugs (bedaquiline, delamanid, linezolid, clofazimine, and fluoroquinolones).

METHODS

We conducted a retrospective cohort study among patients with pulmonary MDR/RR-TB in Georgia who received bedaquiline and delamanid combination as a part of a salvage regimen from November 2017 to December 2020 in a programmatic setting.

RESULTS

Among 106 persons with a median age of 39.5 years, 44 (41.5%) were previously treated with new/companion TB drugs. Patients with prior exposure to new/companion drugs had higher rates of baseline resistance compared to those without exposure to new/companion TB drugs (bedaquiline 15.2% vs 1.8%, linezolid 22.2% vs 16.7%). Sputum culture conversion rates among patients exposed and not exposed to new/companion drugs were 65.9% vs 98.0%, respectively (P < .001). Among patients with and without prior new/companion TB drug use, favorable outcome rates were 41.0% and 82.3%, respectively (P < .001). Treatment adherence in 32 (30.2%) patients was ≤80%. Five of 21 patients (23.8%) who had a baseline and repeat susceptibility test had acquired bedaquiline resistance. QTC/F prolongation (>500 ms) was rare (2.8%).

CONCLUSIONS

Prior exposure to new/companion TB drugs was associated with poor clinical outcomes and acquired drug resistance. Tailoring the TB regimen to each patient's drug susceptibility test results and burden of disease and enhancing adherence support may improve outcomes.

Unraveling Dilemmas and Lacunae in the Escalating Drug Resistance of Mycobacterium tuberculosis to Bedaquiline, Delamanid, and Pretomanid

Delamanid, bedaquiline, and pretomanid have been recently added in the anti-tuberculosis (anti-TB) treatment regimens and have emerged as potential solutions for combating drug-resistant TB. These drugs have proven to be effective in treating drug-resistant TB when used in combination. However, concerns have been raised about the eventual loss of these drugs due to evolving resistance mechanisms and certain adverse effects such as prolonged QT period, gastrointestinal problems, hepatotoxicity, and renal disorders. This Perspective emphasizes the properties of these first-in-class drugs, including their mechanism of action, pharmacokinetics/pharmacodynamics profiles, clinical studies, adverse events, and underlying resistance mechanisms. A brief coverage of efforts toward the generation of best-in-class leads in each class is also provided. The ongoing clinical trials of new combinations of these drugs are discussed, thus providing a better insight into the use of these drugs while designing an effective treatment regimen for resistant TB cases.

Therapeutic Failure and Acquired Bedaquiline and Delamanid Resistance in Treatment of Drug-Resistant TB

New classes of antitubercular drugs, diarylquinolines and nitroimidazoles, have been associated with improved outcomes in the treatment of drug-resistant tuberculosis, but that success is threatened by emerging drug resistance. We report a case of bedaquiline and delamanid resistance in a 55-year-old woman in South Africa with extensively drug-resistant tuberculosis and known HIV.

[Expert consensus on clinical application of delamanid]

Multidrug-resistant tuberculosis(MDR-TB) is a major problem in the prevention and treatment of tuberculosis worldwide, but the treatment success rate is low, and it is necessary to develop new anti-tuberculosis drugs and optimize treatment. Delamanid, a drug with good activity against MDR-TB, has been marketed in recent years. However, there is a lack of clinical medication guidance of delamanid for tuberculosis treatment. To standardize the rational application of delamanid in clinical practice, Chinese Tuberculosis Society organized experts in related fields to issue this consensus. This consensus described the molecular structure, anti-tuberculosis mechanism, pharmacodynamics/pharmacokinetics, drug resistance mechanism, and clinical research of delamanid, put forward recommendations for clinical application, and explained its suitable population, contraindications, methods of application, adverse events, and precautions, so as to provide a reference for clinicians to use delamanid.

Discovery and preclinical evaluations of JBD0131, a novel nitrodihydro-imidazooxazole anti-tuberculosis agent

Multidrug-resistant pulmonary tuberculosis (MDR-TB) is a major health problem worldwide. The treatment for MDR-TB requires medications for a long duration (up to 20-24 months) with second-line drugs resulting in unfavorable outcomes. Nitroimidazoles are promising antimycobacterial agents known to inhibit both aerobic and anaerobic mycobacterial activity. Delamanid and pretomanid are two nitroimidazoles approved by the regulatory agencies for MDR-TB treatment. However, both agents possess unsatisfactory absorption and QTc prolongation. In our search for a safer nitroimidazole, we discovered JBD0131 (2). It exhibited excellent anti-mycobacterial activity against M. tuberculosis H37Rv in vitro and in vivo, improved PK and absorption, reduced QT prolongation potential of delamanid. JBD0131 is currently in clinical development in China for pulmonary tuberculosis (CTR20202308).

OUP accepted manuscript

Given the low treatment success rates of drug-resistant tuberculosis (TB), novel TB drugs are urgently needed. The landscape of TB treatment has changed considerably over the last decade with the approval of three new compounds: bedaquiline, delamanid and pretomanid. Of these, delamanid and pretomanid belong to the same class of drugs, the nitroimidazoles. In order to close the knowledge gap on how delamanid and pretomanid compare with each other, we summarize the main findings from preclinical research on these two compounds. We discuss the compound identification, mechanism of action, drug resistance, in vitro activity, in vivo pharmacokinetic profiles, and preclinical in vivo activity and efficacy. Although delamanid and pretomanid share many similarities, several differences could be identified. One finding of particular interest is that certain Mycobacterium tuberculosis isolates have been described that are resistant to either delamanid or pretomanid, but with preserved susceptibility to the other compound. This might imply that delamanid and pretomanid could replace one another in certain regimens. Regarding bactericidal activity, based on in vitro and preclinical in vivo activity, delamanid has lower MICs and higher mycobacterial load reductions at lower drug concentrations and doses compared with pretomanid. However, when comparing in vivo preclinical bactericidal activity at dose levels equivalent to currently approved clinical doses based on drug exposure, this difference in activity between the two compounds fades. However, it is important to interpret these comparative results with caution knowing the variability inherent in preclinical in vitro and in vivo models.

Efficacy and safety of current medications for treating severe and non-severe COVID-19 patients: an updated network meta-analysis of randomized placebo-controlled trials

BACKGROUND

Many recent studies have investigated the role of drug interventions for coronavirus disease 2019 (COVID-19) infection. However, an important question has been raised about how to select the effective and secure medications for COVID-19 patients. The aim of this analysis was to assess the efficacy and safety of the various medications available for severe and non-severe COVID-19 patients based on randomized placebo-controlled trials (RPCTs).

METHODS

We did an updated network meta-analysis. We searched the databases from inception until July 31, 2021, with no language restrictions. We included RPCTs comparing 49 medications and placebo in the treatment of severe and non-severe patients (aged 18 years or older) with COVID-19 infection. We extracted data on the trial and patient characteristics, and the following primary outcomes: all-cause mortality, the ratios of virological cure, and treatment-emergent adverse events. Odds ratio (OR) and their 95% confidence interval (CI) were used as effect estimates.

RESULTS

From 3,869 publications, we included 61 articles related to 73 RPCTs (57 in non-severe COVID-19 patients and 16 in severe COVID-19 patients), comprising 20,680 patients. The mean sample size was 160 (interquartile range 96-393) in this study. The median duration of follow-up drugs intervention was 28 days (interquartile range 21-30). For increase in virological cure, we only found that proxalutamide (OR 9.16, 95% CI 3.15-18.30), ivermectin (OR 6.33, 95% CI 1.22-32.86), and low dosage bamlanivimab (OR 5.29, 95% CI 1.12-24.99) seemed to be associated with non-severe COVID-19 patients when compared with placebo, in which proxalutamide seemed to be better than low dosage bamlanivimab (OR 5.69, 95% CI 2.43-17.65). For decrease in all-cause mortality, we found that proxalutamide (OR 0.13, 95% CI 0.09-0.19), imatinib (OR 0.49, 95% CI 0.25-0.96), and baricitinib (OR 0.58, 95% CI 0.42-0.82) seemed to be associated with non-severe COVID-19 patients; however, we only found that immunoglobulin gamma (OR 0.27, 95% CI 0.08-0.89) was related to severe COVID-19 patients when compared with placebo. For change in treatment-emergent adverse events, we only found that sotrovimab (OR 0.21, 95% CI 0.13-0.34) was associated with non-severe COVID-19 patients; however, we did not find any medications that presented a statistical difference when compared with placebo among severe COVID-19 patients.

CONCLUSION

We conclude that marked variations exist in the efficacy and safety of medications between severe and non-severe patients with COVID-19. It seems that monoclonal antibodies (e.g., low dosage bamlanivimab, baricitinib, imatinib, and sotrovimab) are a better choice for treating severe or non-severe COVID-19 patients. Clinical decisions to use preferentially medications should carefully consider the risk-benefit profile based on efficacy and safety of all active interventions in patients with COVID-19 at different levels of infection.

QT effects of bedaquiline, delamanid, or both in patients with rifampicin-resistant tuberculosis: a phase 2, open-label, randomised, controlled trial

BACKGROUND

Bedaquiline and delamanid are the first drugs of new classes registered for tuberculosis treatment in 40 years. Each can prolong the QTc interval, with maximum effects occurring weeks after drug initiation. The cardiac safety and microbiological activity of these drugs when co-administered are not well-established. Our aim was to characterise the effects of bedaquiline, delamanid, or both on the QTc interval, longitudinally over 6 months of multidrug treatment, among patients with multidrug-resistant or rifampicin-resistant tuberculosis taking multidrug background therapy.

METHODS

ACTG A5343 is a phase 2, open-label, randomised, controlled trial in which adults with multidrug-resistant or rifampicin-resistant tuberculosis receiving multidrug background treatment were randomly assigned 1:1:1 by centrally, computer-generated randomisation, by means of permuted blocks to receive bedaquiline, delamanid, or both for 24 weeks. Participants were enrolled at TASK in Cape Town and the South African Tuberculosis Vaccine Initiative in Worcester, both in South Africa, and Hospital Maria Auxiliadora in Peru. Individuals with QTc greater than 450 ms were excluded. HIV-positive participants received dolutegravir-based antiretroviral therapy. Clofazimine was disallowed, and levofloxacin replaced moxifloxacin. ECG in triplicate and sputum cultures were done fortnightly. The primary endpoint was mean QTcF change from baseline (averaged over weeks 8-24); cumulative culture conversation at week 8-24 was an exploratory endpoint. Analyses included all participants who initiated study tuberculosis treatment (modified intention-to-treat population). This trial is registered with ClinicalTrials.gov, NCT02583048 and is ongoing.

FINDINGS

Between Aug 26, 2016 and July 13, 2018, of 174 screened, 84 participants (28 in each treatment group, and 31 in total with HIV) were enrolled. Two participants did not initiate study treatment (one in the delamanid group withdrew consent and one in the bedaquiline plus delamanid group) did not meet the eligibility criterion). Mean change in QTc from baseline was 12·3 ms (95% CI 7·8-16·7; bedaquiline), 8·6 ms (4·0-13·1; delamanid), and 20·7 ms (16·1-25·3) (bedaquiline plus delamanid). There were no grade 3 or 4 adverse QTc prolongation events and no deaths during study treatment. Cumulative culture conversion by week 8 was 21 (88%) of 24 (95% CI 71-97; bedaquiline), 20 (83%) of 24 (65-95; delamanid), and 19 (95%) of 20 (79-100; bedaquiline plus delamanid) and was 92% (77-99) for bedaquiline, 91% (76-99), for delamanid, and 95% (79-100) for bedaquiline plus delamanid at 24 weeks.

INTERPRETATION

Combining bedaquiline and delamanid has a modest, no more than additive, effect on the QTc interval, and initial microbiology data are encouraging. This study provides supportive evidence for use of these agents together in patients with multidrug-resistant or rifampicin-resistant tuberculosis with normal baseline QTc values.

FUNDING

Division of AIDS, National Institutes of Health.

Evaluation of Tucatinib in HER2-Positive Breast Cancer Patients With Brain Metastases: A United States-Based Cost-Effectiveness Analysis

PURPOSE

To evaluate the cost-effectiveness of tucatinib in human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC) patients with brain metastases (BMs) and the subgroup of active BMs from the United States (US) payer perspective.

MATERIALS AND METHODS

A 3-state Markov model was developed to compare the cost-effectiveness of 2 regimens in HER2-positive BC patients with BMs: (1) tucatinib, trastuzumab, and capecitabine (TTC); (2) placebo, trastuzumab, and capecitabine (PTC). And subgroup analysis of active BMs was also performed. Lifetime costs, quality-adjusted life years (QALYs), incremental cost-effectiveness ratio (ICER) and incremental net-health benefit (INHB) were estimated. The willingness-to-pay (WTP) threshold was $200,000/QALY. The robustness of the model was tested by sensitivity analyses. Additional scenario analysis was also performed.

RESULTS

Compared with PTC, the ICER yielded by TTC was $418,007.01/QALY and the INHB was -1.08 QALYs in patients with BMs. In the subgroup of active BMs, the ICER and the INHB were $324,465.03/QALY and -0.71 QALY, respectively. The results were most sensitive to the cost of tucatinib. Probabilistic sensitivity analyses suggested that the cost-effective probability of TTC was low at the current WTP threshold in the patients with BMs and the subgroup of active BMs.

CONCLUSION

Tucatinib is unlikely to be cost-effective in HER2-positive BC patients with BMs from the US payer perspective but shows better economics in patients with active BMs. Selecting a favorable population, reducing the price of tucatinib or offering appropriate drug assistance policies might be considerable options to optimize the cost-effectiveness of tucatinib.

Field study to investigate the effectiveness and safety of a novel orally administered combination drug product containing milbemycin oxime and lotilaner (Credelio® Plus) against natural flea and tick infestations on dogs presented as veterinary patients in Europe

BACKGROUND

A pivotal randomised, blinded, positive-controlled, multicentre, European field study was conducted to evaluate the effectiveness and safety of a novel combination tablet of lotilaner and milbemycin oxime (Credelio® Plus) administered orally to client-owned dogs naturally infested with fleas and/or ticks.

METHODS

In this field study, households with flea- or tick-infested dog(s) were enrolled on Day 0 into the study to provide data for either the tick or flea infestation cohorts. Households were randomised in a 2:1 ratio to receive either the combination investigational product (IP, Credelio Plus® tablets) or the control product (CP: Nexgard Spectra® tablets). Dogs were administered IP (flea cohort n = 135; tick cohort: n = 147) or CP (flea cohort: n = 67; tick cohort: n = 74) once every 4 weeks for a total of three times at a dose rate of 20.0-41.5 mg/kg bodyweight lotilaner and 0.75-1.53 mg/kg bodyweight milbemycin oxime (IP) or as recommended (CP). Percentage reduction was calculated by comparing individual dog flea and tick counts at each assessed post-treatment time point to their respective baseline (pre-treatment) infestation. Resolution of the clinical signs of flea allergy dermatitis (FAD) was assessed in flea-allergic dogs on the days that flea counts were performed.

RESULTS

Flea effectiveness of Credelio Plus® after 3 consecutive monthly treatments was 100% against Ctenocephalides felis, C. canis and Pulex irritans. Tick effectiveness of Credelio Plus® over the same time frame was 99.3% for Ixodes ricinus and 100% against Rhipicephalus sanguineus (s.l.). Flea effectiveness of the CP after three consecutive monthly treatments was 100% against C. felis, C. canis and P. irritans. Tick effectiveness of the CP over the same time frame was 99.8% for I. ricinus and 100% against R. sanguineus. Credelio Plus® was well tolerated based on the safety assessments in all treated dogs in this field study. Within both treatment groups there was a reduction in total FAD scores from baseline.

CONCLUSIONS

This pivotal European field study demonstrated the excellent effectiveness and safety of a combination of lotilaner and milbemycin oxime (Credelio Plus®) administered orally to dogs naturally infested with fleas and/or ticks.

Nemiralisib in Patients with an Acute Exacerbation of COPD: Placebo-Controlled, Dose-Ranging Study

Background

Management of acute exacerbations of chronic obstructive pulmonary disease (COPD) is sometimes inadequate leading to either prolonged duration and/or an increased risk of recurrent exacerbations in the period following the initial event.

Objective

To evaluate the safety and efficacy of inhaled nemiralisib, a phosphoinositide 3-kinase δ inhibitor, in patients experiencing an acute exacerbation of COPD.

Patients and Methods

In this double-blind, placebo-controlled study, COPD patients (40-80 years, ≥10 pack-year smoking history, current moderate/severe acute exacerbation of COPD requiring standard-of-care treatment) were randomized to placebo or nemiralisib 12.5 µg, 50 µg, 100 µg, 250 µg, 500 µg, or 750 µg (ratio of 3:1:1:1:1:1:3; N=938) for 12 weeks with an exploratory 12-week follow-up period. The primary endpoint was change from baseline in post-bronchodilator FEV1 at week 12. Key secondary endpoints were rate of re-exacerbations, patient-reported outcomes (Exacerbations of Chronic Pulmonary Disease Tool, COPD Assessment Test, St George's Respiratory Questionnaire-COPD), plasma pharmacokinetics (PK) and safety/tolerability.

Results

There was no difference in change from baseline FEV1 at week 12 between the nemiralisib and placebo treatment groups (posterior adjusted median difference, nemiralisib 750 µg and placebo: -0.004L (95% CrI: -0.051L to 0.042L)). Overall, there were also no differences between nemiralisib and placebo in secondary endpoints, including re-exacerbations. Plasma PK increased in a dose proportional manner. The most common adverse event for nemiralisib was post-inhalation cough which appeared to be dose-related.

Conclusion

The addition of nemiralisib to standard-of-care treatment for 12 weeks did not improve lung function or re-exacerbations in patients with, and following an acute exacerbation of COPD. However, this study demonstrated that large clinical trials recruiting acutely exacerbating patients can successfully be conducted.

Long-term and acute safety of a novel orally administered combination drug product containing milbemycin oxime and lotilaner (Credelio® Plus) in juvenile and adult dogs

BACKGROUND

The combination of milbemycin oxime (MO) and lotilaner (Credelio® Plus) is a novel systemic endectocide that provides month-long effectiveness in dogs after a single oral treatment. The safety of Credelio® Plus flavored chewable tablets was investigated in three target animal safety studies. Two studies (one in juveniles and one in adults) evaluated the long-term safety, and one study evaluated the acute safety of the product when administered orally at the upper end of the recommended dose range (0.75-1.53 mg/kg MO and 20-41 mg/kg lotilaner) and multiples of this dose.

METHODS

The objectives of these studies were to determine the long-term and acute safety of MO and lotilaner flavored chewable tablets in healthy dogs. All three studies were randomized, blinded, parallel-group design studies in healthy Beagle dogs. In each of the two long-term studies, 32 dogs were randomized among four groups to untreated controls or to treated groups at target doses of 1X, 3X, or 5X. Treatment was administered on seven (adult dogs) or nine (juvenile dogs) occasions with dosing every 4 weeks. In the acute study, 48 dogs were randomized among four groups to untreated controls or to treated groups at 1X, 3X, or 6X. In all three studies, the control group was administered placebo tablets. All dogs were fed 30 to 45 min prior to treatment and the assessment of safety was based on health observations, complete physical/neurological examinations, and food consumption. For the long-term safety studies, safety assessments also included clinical pathology evaluations (hematology, clinical chemistry and urinalysis), body weight, pharmacokinetic blood collections, and macroscopic and microscopic examinations of collected tissues.

RESULTS

MO and lotilaner did not induce any treatment-related adverse effects based on health observations, physical/neurological examinations, or food consumption in the long-term or acute studies. Additionally, in the long-term studies, MO and lotilaner did not induce any treatment-related effects on clinical pathology, body weight, and macroscopic and microscopic examinations.

CONCLUSIONS

These three studies demonstrate that Credelio® Plus has a wide safety margin when administered at monthly intervals to puppies and dogs at the high end of the commercial dose band.

Field study to investigate the effectiveness and safety of a novel orally administered combination drug product containing milbemycin oxime and lotilaner (Credelio® Plus) for the prevention of heartworm disease (Dirofilaria immitis) in client-owned dogs in the USA

BACKGROUND

Dirofilaria immitis, a globally distributed filarial parasite of dogs, is known to cause serious or fatal cardiopulmonary disease. Client-owned dogs were enrolled in a clinical field study in the USA to evaluate the clinical effectiveness and field safety of an orally administered combination investigational product (IP) containing milbemycin oxime and lotilaner (Credelio® Plus) as compared to a control product (CP) for the prevention of heartworm disease when administered monthly for 11 consecutive months.

METHODS

In this 11-month field study, 319 dogs ≥ 8 weeks old confirmed to be heartworm-negative were enrolled from eight geographically distinct US veterinary clinics, including sites in the southern USA and Mississippi River Valley. The dogs were treated with either the IP combination product at 0.75-1.53 mg/kg milbemycin oxime and 20-41.5 mg/kg lotilaner (n = 159) or the CP (Sentinel® Flavor Tabs®; milbemycin oxime/lufenuron) at the label-recommended dose rate (n = 158.) On day 330, effectiveness was evaluated in each dog using antigen and microfilarial (modified Knott's) testing to assess the establishment of any patent adult heartworm infections.

RESULTS

All dogs treated with the IP combination product and the CP tested negative (100% prevention) for heartworm infection on day 330. The IP combination product tablets containing milbemycin oxime and lotilaner were well tolerated based on the safety assessments in all treated dogs.

CONCLUSIONS

This multi-site clinical study using client-owned dogs demonstrated that monthly use of flavored, chewable tablets containing a combination of milbemycin oxime and lotilaner administered orally under end use conditions is safe for dogs. None of the enrolled dogs developed heartworm infections. Eleven consecutive monthly treatments of the IP provided 100% prevention of heartworm disease caused by D. immitis.

Outcome of treatment of MDR-TB or drug-resistant patients treated with bedaquiline and delamanid: Results from a large global cohort

The World Health Organization (WHO) recommends countries introduce new anti-TB drugs in the treatment of multidrug-resistant tuberculosis. The aim of the study is to prospectively evaluate the effectiveness of bedaquiline (and/or delamanid)- containing regimens in a large cohort of consecutive TB patients treated globally. This observational, prospective study is based on data collected and provided by Global Tuberculosis Network (GTN) centres and analysed twice a year. All consecutive patients (including children/adolescents) treated with bedaquiline and/or delamanid were enrolled, and managed according to WHO and national guidelines. Overall, 52 centres from 29 countries/regions in all continents reported 883 patients as of January 31st 2021, 24/29 countries/regions providing data on 100% of their consecutive patients (10-80% in the remaining 5 countries). The drug-resistance pattern of the patients was severe (>30% with extensively drug-resistant -TB; median number of resistant drugs 5 (3-7) in the overall cohort and 6 (4-8) among patients with a final outcome). For the patients with a final outcome (477/883, 54.0%) the median (IQR) number of months of anti-TB treatment was 18 (13-23) (in days 553 (385-678)). The proportion of patients achieving sputum smear and culture conversion ranged from 93.4% and 92.8% respectively (whole cohort) to 89.3% and 88.8% respectively (patients with a final outcome), a median (IQR) time to sputum smear and culture conversion of 58 (30-90) days for the whole cohort and 60 (30-100) for patients with a final outcome and, respectively, of 55 (30-90) and 60 (30-90) days for culture conversion. Of 383 patients treated with bedaquiline but not delamanid, 284 (74.2%) achieved treatment success, while 25 (6.5%) died, 11 (2.9%) failed and 63 (16.5%) were lost to follow-up.

A randomized, controlled field study to assess the efficacy and safety of lotilaner flavored chewable tablets (Credelio™ CAT) in eliminating fleas in client-owned cats in the USA

BACKGROUND

Studies show that the novel isoxazoline, lotilaner (Credelio™ CAT; Elanco Animal Health), which is administered orally to cats, provides rapid and sustained flea kill for least 1 month following administration with a wide safety margin. A clinical trial was undertaken to confirm its efficacy, impact on flea allergy dermatitis (FAD) and safety under field conditions.

METHODS

A total of 343 cats were enrolled in the study at 11 veterinary clinics in the USA. Upon inclusion, cat households were randomized at a ratio of 2:1 to receive lotilaner tablets at the recommended dose (minimum 6 mg/kg) or a topical formulation containing fipronil + S-methoprene (Frontline® Plus for cats; Boehringer Ingelheim), administered per label. Owners were dispensed treatments for administration on days 0, 30 and 60; all household cats were administered the same treatment. Flea counts were made on primary cats (1 cat per household) on days 0 (pre-treatment), 30, 60 and 90. Flea allergy dermatitis was assessed on days 30, 60 and 90 for all cats with signs of FAD on day 0. Lotilaner-treated cats were also assessed for their acceptance of oral tablet administration by the pet owner, and safety was assessed for all cats in both groups.

RESULTS

Lotilaner efficacy was 98.3, 99.9 and 99.9% on days 30, 60 and 90, respectively, while the efficacy of fipronil + S-methoprene was 61.6, 75.4 and 84.7%, respectively (P < 0.0001, within both groups and all days). Flea counts were significantly lower in the lotilaner group than in the fipronil + S-methoprene group (P < 0.0001) on each assessment day. On day 90, 98.3% of lotilaner-treated cats and 28.8% of fipronil + S-methoprene-treated cats were free of fleas. Owners successfully administered 99.5% of tablets to their cats. Total FAD score was reduced significantly following treatment in both groups by day 30 (lotilaner: P < 0.0001; fipronil + S-methoprene: P = 0.0041) and continued to decrease following multiple treatments. Total FAD scores were also significantly lower in the lotilaner group than in the fipronil + S-methoprene group on day 90 (P = 0.0006 for FAD total score). Pruritus scores were significantly lower in the lotilaner group on all assessment days.

CONCLUSION

A single lotilaner treatment, administered by the pet owner, was > 98% efficacious in reducing flea counts within 30 days. Three consecutive monthly lotilaner treatments resulted in nearly 100% reduction in flea infestation. In the evaluations of flea counts, number of cats free from fleas and pruritus FAD score, lotilaner was shown to be superior to fipronil + S-methoprene at all time points. Lotilaner was more efficacious than fipronil + S-methoprene and was associated with greater reduction in FAD signs. Lotilaner flavored tablets were well accepted by cats. Adverse reactions were mild and infrequent, confirming the safety of lotilaner tablets in client-owned cats.

Treatment outcomes of children and adolescents receiving drug-resistant TB treatment in a routine TB programme, Mumbai, India

Background

Childhood and adolescent drug-resistant TB (DR-TB) is one of the neglected infectious diseases. Limited evidence exists around programmatic outcomes of children and adolescents receiving DR-TB treatment. The study aimed to determine the final treatment outcomes, culture conversion rates and factors associated with unsuccessful treatment outcome in children and adolescents with DR-TB.

Methods

This is a descriptive study including children (0–9 years) and adolescents (10–19 years) with DR-TB were who were initiated on ambulatory based treatment between January 2017-June 2018 in Shatabdi hospital, Mumbai, India where National TB elimination programme(NTEP) Mumbai collaborates with chest physicians and Médecins Sans Frontières(MSF) in providing comprehensive care to DR-TB patients. The patients with available end-of-treatment outcomes were included. The data was censored on February 2020.

Result

A total of 268 patients were included; 16 (6%) of them were children (0–9 years). The median(min-max) age was 17(4–19) years and 192 (72%) were females. Majority (199, 74%) had pulmonary TB. Most (58%) had MDR-TB while 42% had fluoroquinolone-resistant TB. The median(IQR) duration of treatment (n = 239) was 24(10–25) months. Median(IQR) time for culture-conversion (n = 128) was 3(3–4) months. Of 268 patients, 166(62%) had successful end-of-treatment outcomes (cured-112; completed treatment-54). Children below 10 years had higher proportion of successful treatment outcomes (94% versus 60%) compared to adolescents. Patients with undernutrition [adjusted odds-ratio, aOR (95% Confidence Interval, 95%CI): 2.5 (1.3–4.8) or those with XDR-TB [aOR (95% CI): 4.3 (1.3–13.8)] had higher likelihood of having unsuccessful DR-TB treatment outcome.

Conclusion

High proportion of successful treatment outcome was reported, better than global reports. Further, the nutritional support and routine treatment follow up should be strengthened. All oral short and long regimens including systematic use of new TB drugs (Bedaquiline and Delamanid) should be rapidly scaled up in routine TB programme, especially for the paediatric and adolescent population.

2-Pentadecyl-2-oxazoline ameliorates memory impairment and depression-like behaviour in neuropathic mice: possible role of adrenergic alpha2- and H3 histamine autoreceptors

Neuropathic pain (NP) remains an untreatable disease due to the complex pathophysiology that involves the whole pain neuraxis including the forebrain. Sensory dysfunctions such as allodynia and hyperalgesia are only part of the symptoms associated with neuropathic pain that extend to memory and affectivity deficits. The development of multi-target molecules might be a promising therapeutic strategy against the symptoms associated with NP. 2-pentadecyl-2-oxazoline (PEA-OXA) is a plant-derived agent, which has shown effectiveness against chronic pain and associated neuropsychiatric disorders. The molecular mechanisms by which PEA-OXA exerts its effects are, however, only partially known. In the current study, we show that PEA-OXA, besides being an alpha2 adrenergic receptor antagonist, also acts as a modulator at histamine H3 receptors, and report data on its effects on sensory, affective and cognitive symptoms associated with the spared nerve injury (SNI) model of neuropathic pain in mice. Treatment for 14 days with PEA-OXA after the onset of the symptoms associated with neuropathic pain resulted in the following effects: (i) allodynia was decreased; (ii) affective/cognitive impairment associated with SNI (depression, spatial, and working memories) was counteracted; (iii) long-term potentiation in vivo in the lateral entorhinal cortex-dentate gyrus (perforant pathway, LPP) was ameliorated, (iv) hippocampal glutamate, GABA, histamine, norepinephrine and dopamine level alterations after peripheral nerve injury were reversed, (v) expression level of the TH positive neurons in the Locus Coeruleus were normalized. Thus, a 16-day treatment with PEA-OXA alleviates the sensory, emotional, cognitive, electrophysiological and neurochemical alterations associated with SNI-induced neuropathic pain.

MYCN-Amplified Neuroblastoma Is Addicted to Iron and Vulnerable to Inhibition of the System Xc-/Glutathione Axis

MYCN is amplified in 20% to 25% of neuroblastoma, and MYCN-amplified neuroblastoma contributes to a large percent of pediatric cancer-related deaths. Therapy improvements for this subtype of cancer are a high priority. Here we uncover a MYCN-dependent therapeutic vulnerability in neuroblastoma. Namely, amplified MYCN rewires the cell through expression of key receptors, ultimately enhancing iron influx through increased expression of the iron import transferrin receptor 1. Accumulating iron causes reactive oxygen species (ROS) production, and MYCN-amplified neuroblastomas show enhanced reliance on the system Xc- cystine/glutamate antiporter for ROS detoxification through increased transcription of this receptor. This dependence creates a marked vulnerability to targeting the system Xc-/glutathione (GSH) pathway with ferroptosis inducers. This reliance can be exploited through therapy with FDA-approved rheumatoid arthritis drugs sulfasalazine (SAS) and auranofin: in MYCN-amplified, patient-derived xenograft models, both therapies blocked growth and induced ferroptosis. SAS and auranofin activity was largely mitigated by the ferroptosis inhibitor ferrostatin-1, antioxidants like N-acetyl-L-cysteine, or by the iron scavenger deferoxamine (DFO). DFO reduced auranofin-induced ROS, further linking increased iron capture in MYCN-amplified neuroblastoma to a therapeutic vulnerability to ROS-inducing drugs. These data uncover an oncogene vulnerability to ferroptosis caused by increased iron accumulation and subsequent reliance on the system Xc-/GSH pathway. SIGNIFICANCE: This study shows how MYCN increases intracellular iron levels and subsequent GSH pathway activity and demonstrates the antitumor activity of FDA-approved SAS and auranofin in patient-derived xenograft models of MYCN-amplified neuroblastoma.

Targeting the p300/CBP Axis in Lethal Prostate Cancer

Resistance to androgen receptor (AR) blockade in castration-resistant prostate cancer (CRPC) is associated with sustained AR signaling, including through alternative splicing of AR (AR-SV). Inhibitors of transcriptional coactivators that regulate AR activity, including the paralog histone acetyltransferase proteins p300 and CBP, are attractive therapeutic targets for lethal prostate cancer. Herein, we validate targeting p300/CBP as a therapeutic strategy for lethal prostate cancer and describe CCS1477, a novel small-molecule inhibitor of the p300/CBP conserved bromodomain. We show that CCS1477 inhibits cell proliferation in prostate cancer cell lines and decreases AR- and C-MYC-regulated gene expression. In AR-SV-driven models, CCS1477 has antitumor activity, regulating AR and C-MYC signaling. Early clinical studies suggest that CCS1477 modulates KLK3 blood levels and regulates CRPC biopsy biomarker expression. Overall, CCS1477 shows promise for the treatment of patients with advanced prostate cancer. SIGNIFICANCE: Treating CRPC remains challenging due to persistent AR signaling. Inhibiting transcriptional AR coactivators is an attractive therapeutic strategy. CCS1477, an inhibitor of p300/CBP, inhibits growth and AR activity in CRPC models, and can affect metastatic CRPC target expression in serial clinical biopsies.See related commentary by Rasool et al., p. 1011.This article is highlighted in the In This Issue feature, p. 995.

HER2-positive metastatic breast cancer: a comprehensive review

Cases of human epidermal growth factor receptor 2 (HER2)-positive breast cancer represent approximately 15% to 20% of all breast cancers. Historically, this subtype of breast cancer was associated with an increased risk for the development of systemic and brain metastases and poor overall survival. The introduction of trastuzumab dramatically changed the outcomes of patients with HER2-positive disease, with many demonstrating outcomes similar to those of patients with luminal tumors. Currently, the first-line standard of care for patients with HER2-positive metastatic breast cancer is dual HER2 antibody therapy with pertuzumab/trastuzumab plus a taxane. After progression, the standard of care is trastuzumab emtansine (T-DM1). Although the treatment choices for patients whose disease has progressed on these agents are more limited, promising new drugs have emerged as effective options, including tucatinib and trastuzumab deruxtecan, which were recently approved by the US Food and Drug Administration. Finding the best treatment sequencing for each patient, developing reliable predictive biomarkers, and understanding the mechanisms of resistance to these drugs are necessary to maximize patient outcomes and quality of life. In this review, we analyze the management strategies for metastatic HER2-positive breast cancer, address specific situations, such as the treatment of patients with brain metastases, and discuss future directions in the treatment of this subtype.

Evolution of newer regimens in TB from RNTCP to NTEP

TB is a global disease and the leading cause of death among infectious diseases worldwide. TB was considered incurable till the mid 19th century. The major landmark in the treatment was the discovery of Rifampicin which has led to shorter courses of therapy as compared to the previous regimens which also consisted of injectables. Although, treatment for TB is evolving expeditiously today but a lot needs to be done as far as drug resistant TB (DRTB) is concerned. Non-standard regimens in private sector, lack of access to drug susceptibility testing, delay in the treatment, poor follow up and default in the treatment has led to emergence DRTB. Addition of newer drugs like bedaquiline and delamanid has made oral regimen possible in DRTB as well. Encouraging results of BPaL regimen for extensively drug resistant TB (XDR-TB) may prove to be a game changer. The target of TB elimination by 2025 is onerous considering the huge population, rising DRTB patients and private sector non engagement in the programme despite implementation of second largest national programme of the world.

Pharmacophore modeling, design, and synthesis of potent antihypertensives, oxazolo/thiazolo-[3,2-a]-pyrimidin-3(2H)-one, and 1,5-dihydroimidazo-[1,2-a]-pyrimidin-3(2H)-one derivatives: A pilot trial

An improved pharmacophore model, molecular properties, geometric analyses, and SAR led to synthesize oxazolo/thiazolo-[3,2-a]-pyrimidin-3(2H)-one, and 1,5-dihydroimidazo-[1,2-a]-pyrimidin-3(2H)-one derivatives exhibiting potent anti-hypertensive activity. The 6-ethoxycarbonyl-2,7-dimethyl-5-phenyl-1,5-dihydroimidazo[3,2-a]pyrimidin-3(2H)-one (4g), and 6-ethoxycarbonyl-2,7-dimethyl-5-(3-methyl-phenyl)-1,5-dihydroimidazo[3,2-a]pyrimidin-3(2H)-one (4h) showed significant reduction in mean arterial blood pressure (MABP, mm/Hg) of 79.78%, and 92.95% in 6 and 12 h durations, respectively, at 1.5 mg/kg body-weight dose, while at 3.0 mg/kg body-weight dose, the MABP reduction was achieved at 95.46%, and 92.02%, respectively, in 6 and 12 h durations, as compared to the standard drug, nifedipine.

Neratinib: an option for HER2-positive metastatic breast cancer

Metastatic human epidermal growth factor receptor 2 (HER2)-positive breast cancer is currently incurable. The primary goals of treatment are to prolong survival while optimizing quality of life. Several agents are now available in this setting, including neratinib, tucatinib, ado-trastuzumab emtansine, and trastuzumab deruxtecan. Neratinib in combination with capecitabine was recently approved for the treatment of adult patients with advanced or metastatic breast cancer who have received 2 or more prior anti-HER2-based regimens in the metastatic setting. Neratinib is an oral pan-HER inhibitor that binds covalently to the kinase site, providing irreversible binding. Phase 3 data showed that the combination of neratinib plus capecitabine improved progression-free survival vs lapatinib plus capecitabine. The duration of response was longer among patients in the neratinib arm. Neratinib plus capecitabine was also active against brain metastases associated with refractory, HER2-positive breast cancer, and this combination is listed in guidelines from the National Comprehensive Cancer Network for this indication. When combined with fulvestrant, neratinib demonstrated efficacy in patients with HER2-positive breast cancer, regardless of their hormone receptor status. Ongoing trials are evaluating the ability of neratinib to treat brain metastases, as well as the efficacy and safety of the triplet combination of neratinib, fulvestrant, and trastuzumab in this setting.

Effect of N-palmitoylethanolamine-oxazoline on comorbid neuropsychiatric disturbance associated with inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic disorder characterized by inflammation of the gastrointestinal (GI) tract, and it is associated with different neurological disorders. Recent evidence has demonstrated that the gut-brain-axis has a central function in the perpetuation of IBS, and for this reason, it can be considered a possible therapeutic target. N-Palmitoylethanolamine-oxazoline (PEA-OXA) possesses anti-inflammatory and potent neuroprotective effects. Although recent studies have explained the neuroprotective properties of PEA-OXA, nothing is known about its effects on the gut-brain axis during colitis. The aim of this study is to explore the mechanism and the effect of PEA-OXA on the gut-brain axis in rats subjected to experimental colitis induced by oral administration of dextran sulfate sodium (DSS). Daily oral administration of PEA-OXA (10 mg/kg daily o.s.) was able to decrease the body weight loss, macroscopic damage, colon length, histological alteration, and inflammation after DSS induction. Additionally, PEA-OXA administration enhanced neurotrophic growth factor release and decreased the astroglial and microglial activation induced by DSS. Moreover, PEA-OXA restored intestinal permeability and tight junctions (TJs) as well as reduced apoptosis in the colon and brain. In our work, we demonstrated, for the first time, the action of PEA-OXA on the gut-brain axis in a model of DSS-induced colitis and its implication on the "secondary" effects associated with colonic disturbance.

Acetyl-CoA carboxylase 1 and 2 inhibition ameliorates steatosis and hepatic fibrosis in a MC4R knockout murine model of nonalcoholic steatohepatitis

Acetyl-CoA carboxylase (ACC) catalyzes the rate-limiting step in de novo lipogenesis, which is increased in the livers of patients with nonalcoholic steatohepatitis. GS-0976 (firsocostat), an inhibitor of isoforms ACC1 and ACC2, reduced hepatic steatosis and serum fibrosis biomarkers such as tissue inhibitor of metalloproteinase 1 in patients with nonalcoholic steatohepatitis in a randomized controlled trial, although the impact of this improvement on fibrosis has not fully been evaluated in preclinical models. Here, we used Western diet-fed melanocortin 4 receptor-deficient mice that have similar phenotypes to nonalcoholic steatohepatitis patients including progressively developed hepatic steatosis as well as fibrosis. We evaluated the effects of ACC1/2 inhibition on hepatic fibrosis. After the confirmation of significant hepatic fibrosis with a 13-week pre-feeding, GS-0976 (4 and 16 mg/kg/day) treatment for 9 weeks lowered malonyl-CoA and triglyceride content in the liver and improved steatosis, histologically. Furthermore, GS-0976 reduced the histological area of hepatic fibrosis, hydroxyproline content, mRNA expression level of type I collagen in the liver, and plasma tissue metalloproteinase inhibitor 1, suggesting an improvement of hepatic fibrosis. The treatment with GS-0976 was also accompanied by reductions of plasma ALT and AST levels. These data demonstrate that improvement of hepatic lipid metabolism by ACC1/2 inhibition could be a new option to suppress fibrosis progression as well as to improve hepatic steatosis in nonalcoholic steatohepatitis.

Exposure and response analysis of aleglitazar on cardiovascular risk markers and safety outcomes: An analysis of the AleCardio trial

AIMS

The AleCardio trial aimed to characterize the efficacy and safety of peroxisome proliferator-activated receptor-αγ agonist aleglitazar in patients with type 2 diabetes mellitus and acute coronary syndrome. The trial terminated early because of futility and safety signals. We evaluated whether the safety signals could be attributed to increased exposure to aleglitazar.

MATERIALS AND METHODS

The AleCardio trial enrolled 7226 patients to receive aleglitazar 150 μg or matching placebo on top of standard care. A population pharmacokinetic analysis was conducted in a pharmacokinetic substudy to identify covariates that explained interindividual variability in exposure. Subsequently, the effect of these covariates on surrogate and clinical outcomes was assessed in the full patient population.

RESULTS

Concomitant administration of clopidogrel was identified as a covariate that influenced the apparent clearance of aleglitazar. Patients using clopidogrel had a mean predicted area under the plasma-concentration-time curve (AUC_0-24 ) of 174.7 ng h/mL (SD: ±112.9 ng h/mL) versus 142.2 ng h/mL (SD: ±92.6 ng h/mL) in patients without clopidogrel. The effect of aleglitazar compared with placebo on HbA1c, haemoglobin, serum creatinine and adiponectin was modified by concomitant clopidogrel use (P for interaction 0.007, 0.002, <0.001 and < 0.001, respectively).

CONCLUSIONS

Concomitant use of clopidogrel was identified as a covariate that explained interindividual variability in exposure to aleglitazar. Patients using clopidogrel showed an additional lowering of HbA1c, at the expense of an additional decrease in haemoglobin, and an increase in serum creatinine and adiponectin. Clopidogrel is a moderate inhibitor of CYP2C8. Because aleglitazar is metabolized by CYP2C8, a pharmacokinetic interaction could explain differences in exposure and response to aleglitazar.

The Positive Allosteric Modulator of α2/3-Containing GABAA Receptors, KRM-II-81, Is Active in Pharmaco-Resistant Models of Epilepsy and Reduces Hyperexcitability after Traumatic Brain Injury

The imidizodiazepine, 5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazo[1,5-a][1,4]diazepin-3-yl)oxazole (KRM-II-81), is selective for α2/3-containing GABAA receptors. KRM-II-81 dampens seizure activity in rodent models with enhanced efficacy and reduced motor-impairment compared with diazepam. In the present study, KRM-II-81 was studied in assays designed to detect antiepileptics with improved chances of impacting pharmaco-resistant epilepsies. The potential for reducing neural hyperactivity weeks after traumatic brain injury was also studied. KRM-II-81 suppressed convulsions in corneal-kindled mice. Mice with kainate-induced mesial temporal lobe seizures exhibited spontaneous recurrent hippocampal paroxysmal discharges that were significantly reduced by KRM-II-81 (15 mg/kg, orally). KRM-II-81 also decreased convulsions in rats undergoing amygdala kindling in the presence of lamotrigine (lamotrigine-insensitive model) (ED50 = 19 mg/kg, i.p.). KRM-II-81 reduced focal and generalized seizures in a kainate-induced chronic epilepsy model in rats (20 mg/kg, i.p., three times per day). In mice with damage to the left cerebral cortex by controlled-cortical impact, enduring neuronal hyperactivity was dampened by KRM-II-81 (10 mg/kg, i.p.) as observed through in vivo two-photon imaging of layer II/III pyramidal neurons in GCaMP6-expressing transgenic mice. No notable side effects emerged up to doses of 300 mg/kg KRM-II-81. Molecular modeling studies were conducted: docking in the binding site of the α1β3γ2L GABAA receptor showed that replacing the C8 chlorine atom of alprazolam with the acetylene of KRM-II-81 led to loss of the key interaction with α1His102, providing a structural rationale for its low affinity for α1-containing GABAA receptors compared with benzodiazepines such as alprazolam. Overall, these findings predict that KRM-II-81 has improved therapeutic potential for epilepsy and post-traumatic epilepsy. SIGNIFICANCE STATEMENT: We describe the effects of a relatively new orally bioavailable small molecule in rodent models of pharmaco-resistant epilepsy and traumatic brain injury. KRM-II-81 is more potent and generally more efficacious than standard-of-care antiepileptics. In silico docking experiments begin to describe the structural basis for the relative lack of motor impairment induced by KRM-II-81. KRM-II-81 has unique structural and anticonvulsant effects, predicting its potential as an improved antiepileptic drug and novel therapy for post-traumatic epilepsy.

Antagonism of the Thromboxane-Prostanoid Receptor as a Potential Therapy for Cardiomyopathy of Muscular Dystrophy

Background Muscular dystrophy (MD) causes a progressive cardiomyopathy characterized by diffuse fibrosis, arrhythmia, heart failure, and early death. Activation of the thromboxane-prostanoid receptor (TPr) increases calcium transients in cardiomyocytes and is proarrhythmic and profibrotic. We hypothesized that TPr activation contributes to the cardiac phenotype of MD, and that TPr antagonism would improve cardiac fibrosis and function in preclinical models of MD. Methods and Results Three different mouse models of MD (mdx/utrn double knockout, second generation mdx/mTR double knockout, and delta-sarcoglycan knockout) were given normal drinking water or water containing 25 mg/kg per day of the TPr antagonist ifetroban, beginning at weaning. After 6 months (10 weeks for mdx/utrn double knockout), mice were evaluated for cardiac and skeletal muscle function before euthanization. There was a 100% survival rate of ifetroban-treated mice to the predetermined end point, compared with 60%, 43%, and 90% for mdx/utrn double knockout, mdx/mTR double knockout, and delta-sarcoglycan knockout mice, respectively. TPr antagonism improved cardiac output in mdx/utrn double knockout and mdx/mTR mice, and normalized fractional shortening, ejection fraction, and other parameters in delta-sarcoglycan knockout mice. Cardiac fibrosis in delta-sarcoglycan knockout was reduced with TPr antagonism, which also normalized cardiac expression of claudin-5 and neuronal nitric oxide synthase proteins and multiple signature genes of Duchenne MD. Conclusions TPr antagonism reduced cardiomyopathy and spontaneous death in mouse models of Duchenne and limb-girdle MD. Based on these studies, ifetroban and other TPr antagonists could be novel therapeutics for treatment of the cardiac phenotype in patients with MD.

The next-generation BET inhibitor, PLX51107, delays melanoma growth in a CD8-mediated manner

Epigenetic agents such as bromodomain and extra-terminal region inhibitors (BETi) slow tumor growth via tumor intrinsic alterations; however, their effects on antitumor immunity remain unclear. A recent advance is the development of next-generation BETi that are potent and display a favorable half-life. Here, we tested the BETi, PLX51107, for immune-based effects on tumor growth in BRAF V600E melanoma syngeneic models. PLX51107 delayed melanoma tumor growth and increased activated, proliferating, and functional CD8+ T cells in tumors leading to CD8+ T-cell-mediated tumor growth delay. PLX51107 decreased Cox2 expression, increased dendritic cells, and lowered PD-L1, FasL, and IDO-1 expression in the tumor microenvironment. Importantly, PLX51107 delayed the growth of tumors that progressed on anti-PD-1 therapy; a response associated with decreased Cox2 levels, decreased PD-L1 expression on non-immune cells, and increased intratumoral CD8+ T cells. Thus, next-generation BETi represent a potential first-line and secondary treatment strategy for metastatic melanoma by eliciting effects, at least in part, on antitumor CD8+ T cells.

The α2,3-selective potentiator of GABAA receptors, KRM-II-81, reduces nociceptive-associated behaviors induced by formalin and spinal nerve ligation in rats

Clinical evidence indicates that positive allosteric modulators (PAMs) of GABAA receptors have analgesic benefit in addition to efficacy in anxiety disorders. However, the utility of GABAA receptor PAMs as analgesics is compromised by the central nervous system side effects of non-selective potentiators. A selective potentiator of GABAA receptors associated with α2/3 subunits, KRM-II-81(5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazo[1,5-a][1,4]diazepin-3-yl)oxazole), has demonstrated anxiolytic, anticonvulsant, and antinociceptive effects in rodents with reduced motoric side effects. The present study evaluated the potential of KRM-II-81 as a novel analgesic. Oral administration of KRM-II-81 attenuated formalin-induced flinching; in contrast, diazepam was not active. KRM-II-81 attenuated nociceptive-associated behaviors engendered by chronic spinal nerve ligation (L5/L6). Diazepam decreased locomotion of rats at the dose tested in the formalin assay (10 mg/kg) whereas KRM-II-81 produced small decreases that were not dose-dependent (10-100 mg/kg). Plasma and brain levels of KRM-II-81 were used to demonstrate selectivity for α2/3- over α1-associated GABAA receptors and to define the degree of engagement of these receptors. Plasma and brain concentrations of KRM-II-81 were positively-associated with analgesic efficacy. GABA currents from isolated rat dorsal-root ganglion cultures were potentiated by KRM-II-81 with an ED50 of 32 nM. Measures of respiratory depression were reduced by alprazolam whereas KRM-II-81 was either inactive or produced effects with lower potency and efficacy. These findings add to the growing body of data supporting the idea that α2/3-selective GABAA receptor PAMs will have efficacy and tolerability as pain medications including those for neuropathic pain. Given their predicted anxiolytic effects, α2/3-selective GABAA receptor PAMs offer an additional inroad into the management of pain.

Early efficacy and safety of Bedaquiline and Delamanid given together in a "Salvage Regimen" for treatment of drug-resistant tuberculosis

BACKGROUND

Drug-Resistant Tuberculosis (DR-TB) patients for whom a WHO recommended regimen along with Bedaquiline (BDQ) cannot be prescribed, Delamanid (DLM) was added along with other drugs to provide a "Salvage Regimen". The experience of the Institute in respect of early efficacy and safety of both drugs given together is presented.

OBJECTIVE

To ascertain the early efficacy, safety and tolerability of Bedaquline and Delamanid given together as a part of salvage regimen.

METHODS

BDQ and DLM were used together to make regimens along with other drugs where four effective anti TB drugs could not be prescribed as per WHO recommendations. Patients were followed up for sputum smear and culture conversion and adverse events during the treatment.

RESULTS

In this cohort study, 53 DR-TB patients (Median age-24) were initiated on regimens containing both BDQ and DLM. Sputum smear conversion was seen in 35% and 94% patients at the end of 1st week and 3rd month respectively. 84% patients had culture conversion at the end of 4th month. 29 adverse events (AE) were reported among 17 patients and there were 11 deaths. QTc prolongation more than 500 MS was seen in only 1 patient.

CONCLUSION

BDQ and DLM given together in a salvage regimen is efficacious with low rate of adverse events. The combination provides hope to DR-TB patients with limited treatment options and should be provided as a life saving option.

Building upon Nature's Framework: Overview of Key Strategies Toward Increasing Drug-Like Properties of Natural Product Cyclopeptides and Macrocycles

The pharmaceutical industry has focused mainly in the development of small-molecule entities intended for oral administration for the past decades. As a result, the majority of existing drugs address only a narrow range of biological targets. In the era of post-genomics, transcriptomics, and proteomics, there is an increasing interest on larger modulators of proteins that can span larger surfaces, access new therapeutic mechanisms of action, and provide greater target specificity. Traditional drug-like molecules developed using "rule-of-five" (Ro5) guidelines have been proven ineffective against a variety of challenging targets, such as protein-protein interactions, nucleic acid complexes, and antibacterial modalities. However, natural products are known to be effective at modulating such targets, leading to a renewed focus by medicinal chemists on investigating underrepresented chemical scaffolds associated with natural products. Here we describe recent efforts toward identification of novel natural cyclopeptides and macrocycles as well as selected medicinal chemistry strategies to increase drug-like properties or further exploration of their activity.

Monoamine oxidase inhibitors protect against coronary heart disease in rodent rat models: A pilot study

The present study designed to investigate the effect of monoamine oxidase inhibitor in the rat model of Coronary heart disease (cardiac hypertrophy). A total of 40 male adult Wistar rats having body weight 300-400 gram were equally distributed in two groups (Test group: Rats with Angiotensin II + monoamine oxidase inhibitor (Befloxatone); Reference group: Rats with cardiac hypertrophy induced by Angiotensin II). Rat model of cardiac hypertrophy were induced by Angiotensin II. Effect of Befloxatone on cardiac hypertrophy was evaluated by electrocardiography, hemodynamic and histological assessment. Vital signs such as pulse rate, and blood pressure were measured. Echocardiographic related variable including ejection fraction were also assessed in both the groups. Also, expression of monoamine oxidase was analyzed using by real-time-PCR and Western blot analysis. In results, we found following 1) monoamine oxidase inhibitor treatment prevents Angiotensin II induced increase in level of ANP and βeta-myosin, which are responsible for inducing cardiac hypertrophic responses; 2) monoamine oxidase inhibitor ameliorates Angiotensin II induced cell enlargement by reducing the surface area of cells; 3) monoamine oxidase inhibitor attenuates the hypertrophic response triggered by Angiotensin II; 4) monoamine oxidase inhibitor ameliorates increased heart rate and average arterial pressure induced by angiotensin II; 5) Overall finding suggested that monoamine oxidase inhibitor improves left ventricle hypertrophy and ejection fraction by inhibiting monoamine oxidase enzyme in heart. The finding of this study gives the new vision to cardiovascular researchers to develop anti- hypertrophy therapy based on monoamine oxidase inhibition.

Undergraduate Medical Teaching: Time to integrate?

Delamanid is a nitro-dihydro-imidazooxazole compound which was developed by a Japanese company, Otsuka Holdings inc. and has shown in-vitro and in-vivo activity against drug resistant tuberculosis. The drug exerts its anti-mycobacterial activity by inhibition of mycolic acid biosynthesis, leading to defective cell wall formation ultimately leading to bacterial death. Following the promising results in Phase 2 trials, Delamanid received approval in European Union in 2014, following which it was also approved in Japan and Korea in the same year. It was approved in India recently in August, 2017. Though relatively well tolerated, there have been concerns due to QT prolongation associated with the use of Delamanid. WHO has currently recommended use of Delamanid in combination with optimized background regimen in patients with pulmonary TB (conditional recommendation). More data from clinical trials and observational studies is awaited regarding use of Delamanid in children, HIV co-infection, pregnant women and use in combination with Bedaquiline.

Homeostasis Model Assessment of Insulin Resistance and Survival in Patients With Diabetes and Acute Coronary Syndrome

OBJECTIVE

Insulin resistance has been linked to development and progression of atherosclerosis and is present in most patients with type 2 diabetes. Whether the degree of insulin resistance predicts adverse outcomes in patients with type 2 diabetes and acute coronary syndrome (ACS) is uncertain.

DESIGN

The Effect of Aleglitazar on Cardiovascular Outcomes after Acute Coronary Syndrome in Patients with Type 2 Diabetes Mellitus trial compared the peroxisome proliferator-activated receptor-α/γ agonist aleglitazar with placebo in patients with type 2 diabetes and recent ACS. In participants not treated with insulin, we determined whether baseline homeostasis model assessment of insulin resistance (HOMA-IR; n = 4303) or the change in HOMA-IR on assigned study treatment (n = 3568) was related to the risk of death or major adverse cardiovascular events (cardiovascular death, myocardial infarction, and stroke) in unadjusted and adjusted models. Because an inverse association of HOMA-IR with N-terminal pro-B-type natriuretic peptide (NT-proBNP) has been described, we specifically examined effects of adjustment for the latter.

RESULTS

In unadjusted analysis, twofold higher baseline HOMA-IR was associated with lower risk of death [hazard ratio (HR): 0.79, 95% CI: 0.68 to 0.91, P = 0.002]. Adjustment for 24 standard demographic and clinical variables had minimal effect on this association. However, after further adjustment for NT-proBNP, the association of HOMA-IR with death was no longer present (adjusted HR: 0.99, 95% CI: 0.83 to 1.19, P = 0.94). Baseline HOMA-IR was not associated with major adverse cardiovascular events, nor was the change in HOMA-IR on study treatment associated with death or major adverse cardiovascular events.

CONCLUSIONS

After accounting for levels of NT-proBNP, insulin resistance assessed by HOMA-IR is not related to the risk of death or major adverse cardiovascular events in patients with type 2 diabetes and ACS.

Current Status of Delamanid in the Management of MDR Tuberculosis

Delamanid is a nitro-dihydro-imidazooxazole compound which was developed by a Japanese company, Otsuka Holdings inc. and has shown in-vitro and in-vivo activity against drug resistant tuberculosis. The drug exerts its anti-mycobacterial activity by inhibition of mycolic acid biosynthesis, leading to defective cell wall formation ultimately leading to bacterial death. Following the promising results in Phase 2 trials, Delamanid received approval in European Union in 2014, following which it was also approved in Japan and Korea in the same year. It was approved in India recently in August, 2017. Though relatively well tolerated, there have been concerns due to QT prolongation associated with the use of Delamanid. WHO has currently recommended use of Delamanid in combination with optimized background regimen in patients with pulmonary TB (conditional recommendation). More data from clinical trials and observational studies is awaited regarding use of Delamanid in children, HIV co-infection, pregnant women and use in combination with Bedaquiline.

New and repurposed drugs to treat multidrug- and extensively drug-resistant tuberculosis

Multidrug-resistant and extensively drug-resistant tuberculosis (MDR-TB and XDR-TB, respectively) continue to represent a challenge for clinicians and public health authorities. Unfortunately, although there have been encouraging reports of higher success rates, the overall rate of favorable outcomes of M/XDR-TB treatment is only 54%, or much lower when the spectrum of drug resistance is beyond that of XDR-TB. Treating M/XDR-TB continues to be a difficult task, because of the high incidence of adverse events, the long duration of treatment, the high cost of the regimens used, and the drain on health care resources. Various trials and studies have recently been undertaken (some already published and others ongoing), all aimed at improving outcomes of M/XDR-TB treatment by changing the overall approach, shortening treatment duration, and developing a universal regimen. The objective of this review was to summarize what has been achieved to date, as far as new and repurposed drugs are concerned, with a special focus on delamanid, bedaquiline, pretomanid, clofazimine, carbapenems, and linezolid. After more than 40 years of neglect, greater attention has recently been paid to the need for new drugs to fight the "white plague", and promising results are being reported.

Predictors of mortality in hospital survivors with type 2 diabetes mellitus and acute coronary syndromes

AIM

To define the predictors of long-term mortality in patients with type 2 diabetes mellitus and recent acute coronary syndrome.

METHODS AND RESULTS

A total of 7226 patients from a randomized trial, testing the effect on cardiovascular outcomes of the dual peroxisome proliferator-activated receptor agonist aleglitazar in patients with type 2 diabetes mellitus and recent acute coronary syndrome (AleCardio trial), were analysed. Median follow-up was 2 years. The independent mortality predictors were defined using Cox regression analysis. The predictive information provided by each variable was calculated as percent of total chi-square of the model. All-cause mortality was 4.0%, with cardiovascular death contributing for 73% of mortality. The mortality prediction model included N-terminal proB-type natriuretic peptide (adjusted hazard ratio = 1.68; 95% confidence interval = 1.51-1.88; 27% of prediction), lack of coronary revascularization (hazard ratio = 2.28; 95% confidence interval = 1.77-2.93; 18% of prediction), age (hazard ratio = 1.04; 95% confidence interval = 1.02-1.05; 15% of prediction), heart rate (hazard ratio = 1.02; 95% confidence interval = 1.01-1.03; 10% of prediction), glycated haemoglobin (hazard ratio = 1.11; 95% confidence interval = 1.03-1.19; 8% of prediction), haemoglobin (hazard ratio = 1.01; 95% confidence interval = 1.00-1.02; 8% of prediction), prior coronary artery bypass (hazard ratio = 1.61; 95% confidence interval = 1.11-2.32; 7% of prediction) and prior myocardial infarction (hazard ratio = 1.40; 95% confidence interval = 1.05-1.87; 6% of prediction).

CONCLUSION

In patients with type 2 diabetes mellitus and recent acute coronary syndrome, mortality prediction is largely dominated by markers of cardiac, rather than metabolic, dysfunction.

An open-label study to assess the feasibility and tolerability of rilmenidine for the treatment of Huntington's disease

Preclinical data have shown that rilmenidine can regulate autophagy in models of Huntington's disease (HD), providing a potential route to alter the disease course in patients. Consequently, a 2-year open-label study examining the tolerability and feasibility of rilmenidine in mild-moderate HD was undertaken. 18 non-demented patients with mild to moderate HD took daily doses of 1 mg Rilmenidine for 6 months and 2 mg for a further 18 months followed by a 3-month washout period. The primary outcome was the number of withdrawals and serious adverse events. Secondary outcomes included safety parameters and changes in disease-specific variables, such as motor, cognitive and functional performance, structural MRI and serum metabolomic analysis. 12 patients completed the study; reasons for withdrawal included problems tolerating study procedures (MRI, and venepuncture), depression requiring hospital admission and logistical reasons. Three serious adverse events were recorded, including hospitalisation for depression, but none were thought to be drug-related. Changes in secondary outcomes were analysed as the annual rate of change in the study group. The overall change was comparable to changes seen in recent large observational studies in HD patients, though direct statistical comparisons to these studies were not made. Chronic oral administration of rilmenidine is feasible and well-tolerated and future, larger, placebo-controlled, studies in HD are warranted.

TRIAL REGISTRATION

EudraCT number 2009-018119-14.

Outpatient treatment of acute bacterial skin and skin structure infections (ABSSSI) with tedizolid phosphate and linezolid in patients in the United States: Subgroup analysis of 2 randomized phase 3 trials

BACKGROUND

Acute bacterial skin and skin structure infections (ABSSSI) are a frequent cause of hospital admissions in the United States. Safe and effective outpatient treatments may lower ABSSSI-associated health care costs by reducing unnecessary hospital admissions. Using data from 2 phase 3 trials (ESTABLISH-1, NCT01170221; ESTABLISH-2, NCT01421511), this post-hoc analysis explored the efficacy and safety of tedizolid in an outpatient setting.

METHODS

Subgroup analysis was performed on US outpatients (defined as patients who were not in hospital at the time of treatment initiation) with ABSSSI caused by presumed or proven gram-positive pathogens. Patients were randomly assigned to receive tedizolid phosphate 200 mg once daily for 6 days (n = 403) or linezolid 600 mg twice daily for 10 days (n = 410). The primary end point was early clinical response (48-72 hours after the start of treatment). Secondary end points included investigator-assessed clinical response at end of therapy (EOT) and post-therapy evaluation (PTE; 7-14 days after therapy). Additional assessments included the patient-reported level of pain using a visual analog scale (VAS) and the per-pathogen favorable microbiological response rate at the PTE visit. Compliance with treatment and safety outcomes was also recorded.

RESULTS

Early clinical response was similar between treatment groups (tedizolid, 82.4%; linezolid, 79.0%), as was investigator-assessed clinical response at EOT (tedizolid, 87.1%; linezolid, 86.1%) and PTE (tedizolid, 83.1%; linezolid, 83.7%). Mean changes from baseline to days 10 to 13 in VAS scores were identical between treatment groups (tedizolid, -51.9 mm; linezolid, -51.9 mm). Microbiological eradication rates were generally similar in both treatment groups for all key pathogens. Patients in both groups had favorable response at PTE. More tedizolid-treated patients (89.3%) than linezolid-treated patients (77.3%) were compliant with treatment. The most frequently reported drug-related treatment-emergent adverse events were nausea (tedizolid, 10.7%; linezolid, 13.8%), diarrhea (tedizolid, 4.5%; linezolid, 5.9%), and headache (tedizolid, 5.5%; linezolid, 4.4%). Treatment discontinuation rates were low for both treatment groups (tedizolid, 0.7%; linezolid, 1.0%).

CONCLUSION

Short-course therapy with tedizolid can successfully treat patients with ABSSSI caused by presumed or proven gram-positive pathogens in an outpatient setting.

Six-Month Response to Delamanid Treatment in MDR TB Patients

Delamanid, recently available for the treatment of multidrug-resistant tuberculosis (MDR TB), has had limited use outside clinical trials. We present the early treatment results for 53 patients from 7 countries who received a delamanid-containing treatment for MDR TB. Results show good tolerability and treatment response at 6 months.

Bedaquiline and Delamanid Combination Treatment of 5 Patients with Pulmonary Extensively Drug-Resistant Tuberculosis

We report the experiences of 5 patients taking bedaquiline with delamanid in combination: 1 patient was cured; 3 culture converted, with 2 continuing and 1 changing therapy; and 1 died from respiratory insufficiency. For 2 patients, QT-interval prolongation but no arrhythmias occurred. Use of this therapy is justified for patients with limited options.

Current therapies for the treatment of multidrug-resistant tuberculosis in children in India

INTRODUCTION

Multidrug-resistant tuberculosis (MDR-TB) is a serious life threatening condition affecting children as well as adults worldwide. Timely diagnosis and effective treatment, both of which are complex in children, are the prerogatives for a favorable outcome. Areas covered: This review covers epidemiology, treatment regimen and duration, newer drugs and adverse events in children with MDR-TB. Special note has been made of epidemiology and principles of treatment followed in Indian children. Expert opinion: High index of suspicion is essential for diagnosing childhood MDR-TB. If there is high probability, a child can be diagnosed as presumptive MDR-TB and started on empiric treatment in consultation with experts. However, every effort should be made to confirm the diagnosis. Backbone of an effective MDR-TB regimen consists of four 2nd line anti-TB drugs plus pyrazinamide; duration being 18-24 months. The newer drugs delamanid and bedaquiline can be used in younger children if no other alternatives are available after consultation with experts. Wider availability of these drugs should be ensured for benefit to all concerned. More research is required for development of new and repurposed drugs to combat MDR-TB. Children need to be included in clinical trials for such life-saving drugs, so that nobody is denied the benefits.

Effects of Tedizolid Phosphate on Survival Outcomes and Suppression of Production of Staphylococcal Toxins in a Rabbit Model of Methicillin-Resistant Staphylococcus aureus Necrotizing Pneumonia

The protective efficacy of tedizolid phosphate, a novel oxazolidinone that potently inhibits bacterial protein synthesis, was compared to those of linezolid, vancomycin, and saline in a rabbit model of Staphylococcus aureus necrotizing pneumonia. Tedizolid phosphate was administered to rabbits at 6 mg/kg of body weight intravenously twice daily, which yielded values of the 24-h area under the concentration-time curve approximating those found in humans. The overall survival rate was 83% for rabbits treated with 6 mg/kg tedizolid phosphate twice daily and 83% for those treated with 50 mg/kg linezolid thrice daily (P = 0.66 by the log-rank test versus the results obtained with tedizolid phosphate). These survival rates were significantly greater than the survival rates of 17% for rabbits treated with 30 mg/kg vancomycin twice daily (P = 0.003) and 17% for rabbits treated with saline (P = 0.002). The bacterial count in the lungs of rabbits treated with tedizolid phosphate was significantly decreased compared to that in the lungs of rabbits treated with saline, although it was not significantly different from that in the lungs of rabbits treated with vancomycin or linezolid. The in vivo bacterial production of alpha-toxin and Panton-Valentine leukocidin, two key S. aureus-secreted toxins that play critical roles in the pathogenesis of necrotizing pneumonia, in the lungs of rabbits treated with tedizolid phosphate and linezolid was significantly inhibited compared to that in the lungs of rabbits treated with vancomycin or saline. Taken together, these results indicate that tedizolid phosphate is superior to vancomycin for the treatment of S. aureus necrotizing pneumonia because it inhibits the bacterial production of lung-damaging toxins at the site of infection.

[New antibiotics - standstill or progress]

The development of resistance to antibiotics has been ignored for a long time. But nowadays, increasing resistance is an important topic. For a decade no new antibiotics had been developed and it is not possible to quickly close this gap of new resistance and no new drugs. This work presents six new antibiotics (ceftaroline, ceftobiprole, solithromycin, tedizolid, ceftolozane/tazobactam, ceftazidime/avibactam). In part, only expert opinions are given due to lack of study results.The two 5th generation cephalosporins ceftaroline and ceftobiprole have beside their equivalent efficacy to ceftriaxone (ceftaroline) and cefipim (ceftobiprole) high activity against MRSA. The fluoroketolide solithromycin should help against macrolide-resistant pathogens and has been shown to be noninferior to the fluorochinolones. The oxazolidinone tedizolid is effective against linezolid-resistant MRSA. The two cephalosporins ceftolozane/tazobactam and ceftazidime/avibactam are not only effective against gram-negative pathogens, but they have a very broad spectrum. Due to the efficacy against extended-spectrum β‑lactamases, they can relieve the selection pressure of the carbapenems. We benefit from all new antibiotics which can take the selection pressure from other often used antibiotics. The increasing number of resistant gram-negative pathogens worldwide is alarming. Thus, focusing on the development of new drugs is extremely important.

Efficacy of tedizolid against methicillin-resistant Staphylococcus aureus and Peptostreptococcus anaerobius in thigh mixed-infection mouse model

OBJECTIVE

The purpose of this study is to compare the antimicrobial activity of human simulated exposures of tedizolid 200 mg daily, and linezolid 600 mg every 12 h for the treatment of complicated skin and skin structure infection (cSSSI) caused by MRSA and Peptostreptococcus anaerobius in both the neutropenic mice thigh mixed-infection models.

MATERIAL AND METHOD

Tedizolid phosphate and linezolid were used for all in vivo testing. A total of one MRSA and two P. anaerobius isolates were utilized. Antimicrobial efficacy was calculated for each isolate as the change in bacterial numbers (Δlog₁₀ CFU/ml) obtained in the treated mice after 24 h compared with the numbers in the starting control animals (0 h).

RESULTS

The tedizolid and linezolid MICs for MRSA was 0.25 and 2 μg/ml. Tedizolid MIC for P. anaerobius was 0.12 μg/ml, and linezolid MICs for two P. anaerobius isolates were 0.5 and 1 μg/ml. In mixed infection model, tedizolid therapy showed similar antimicrobial activities for one MRSA and two P. anaerobius isolates evaluated, compared with linezolid therapy. Additionally, when comparing the activity of tedizolid and linezolid monotherapy between single infection and mixed infection model, antimicrobial activities of both antimicrobials were attenuated when mixed infection model was used.

CONCLUSION

In the neutropenic murine thigh infection model, human simulated exposures of tedizolid and linezolid resulted in similar efficacies against MRSA, even though single and mixed infection models were used. These data support the clinical utility of tedizolid for use against MRSA and P. anaerobius in the treatment of cSSSI.