Enzymatic Strategies for the Preparation of Pharmaceutically Important Amino Acids through Hydrolysis of Amino Carboxylic Esters and Lactams.

The most relevant lipase-catalyzed strategies for the synthesis of pharmaceutically important cyclic and acyclic α-, ß- and γ-amino carboxylic acid enantiomers through hydrolysis of the corresponding amino carboxylic esters and lactams, over the last decade are overviewed. A brief Introduction part deals with the importance and synthesis of enantiomeric amino acids, and formulates the objectives of the actual work. The strategies are presented in the Main Text, in chronological order, classified as kinetic, dynamic kinetic and sequential kinetic resolution. Mechanistic information of the enzymatic transformations is also available at the end of this overview. The pharmacological importance of the enantiomeric amino acids is given next to their synthesis, in the Main Text, and it is also illustrated in the Conclusions and Outlook sections.

Physiologically-Based Pharmacokinetic-Led Guidance for Patients With Cystic Fibrosis Taking Elexacaftor-Tezacaftor-Ivacaftor With Nirmatrelvir-Ritonavir for the Treatment of COVID-19.

Cystic fibrosis transmembrane conductance regulator (CFTR) modulating therapies, including elexacaftor-tezacaftor-ivacaftor, are primarily eliminated through cytochrome P450 (CYP) 3A-mediated metabolism. This creates a therapeutic challenge to the treatment of coronavirus disease 2019 (COVID-19) with nirmatrelvir-ritonavir in people with cystic fibrosis (CF) due to the potential for significant drug-drug interactions (DDIs). However, the population with CF is more at risk of serious illness following COVID-19 infection and hence it is important to manage the DDI risk and provide treatment options. CYP3A-mediated DDI of elexacaftor-tezacaftor-ivacaftor was evaluated using a physiologically-based pharmacokinetic modeling approach. Modeling was performed incorporating physiological information and drug-dependent parameters of elexacaftor-tezacaftor-ivacaftor to predict the effect of ritonavir (the CYP3A inhibiting component of the combination) on the pharmacokinetics of elexacaftor-tezacaftor-ivacaftor. The elexacaftor-tezacaftor-ivacaftor models were verified using independent clinical pharmacokinetic and DDI data of elexacaftor-tezacaftor-ivacaftor with a range of CYP3A modulators. When ritonavir was administered on Days 1 through 5, the predicted area under the curve (AUC) ratio of ivacaftor (the most sensitive CYP3A substrate) on Day 6 was 9.31, indicating that its metabolism was strongly inhibited. Based on the predicted DDI, the dose of elexacaftor-tezacaftor-ivacaftor should be reduced when coadministered with nirmatrelvir-ritonavir to elexacaftor 200 mg-tezacaftor 100 mg-ivacaftor 150 mg on Days 1 and 5, with delayed resumption of full-dose elexacaftor-tezacaftor-ivacaftor on Day 9, considering the residual inhibitory effect of ritonavir as a mechanism-based inhibitor. The simulation predicts a regimen of elexacaftor-tezacaftor-ivacaftor administered concomitantly with nirmatrelvir-ritonavir in people with CF that will likely decrease the impact of the drug interaction.

The oral protease inhibitor (PF-07321332) protects Syrian hamsters against infection with SARS-CoV-2 variants of concern.

There is an urgent need for potent and selective antivirals against SARS-CoV-2. Pfizer developed PF-07321332 (PF-332), a potent inhibitor of the viral main protease (Mpro, 3CLpro) that can be dosed orally and that is in clinical development. We here report that PF-332 exerts equipotent in vitro activity against the four SARS-CoV-2 variants of concerns (VoC) and that it can completely arrest replication of the alpha variant in primary human airway epithelial cells grown at the air-liquid interface. Treatment of Syrian Golden hamsters with PF-332 (250 mg/kg, twice daily) completely protected the animals against intranasal infection with the beta (B.1.351) and delta (B.1.617.2) SARS-CoV-2 variants. Moreover, treatment of SARS-CoV-2 (B.1.617.2) infected animals with PF-332 completely prevented transmission to untreated co-housed sentinels.

A Phase I Study to Evaluate the Pharmacokinetics and Safety of Lorlatinib in Adults with Mild, Moderate, and Severe Renal Impairment.

BACKGROUND AND OBJECTIVES: Lorlatinib is approved (100 mg once daily [QD]) for the treatment of patients with anaplastic lymphoma kinase- (ALK) positive metastatic non-small cell lung cancer. This study evaluated the impact of varying degrees of renal impairment on the safety and pharmacokinetics of lorlatinib. METHODS: Participants were assigned to mild, moderate, and severe renal impairment groups and to a matching normal renal function group based on absolute estimated glomerular filtration rate (eGFR, based on the Modification of Diet in Renal Disease equation and adjusted for body surface area [BSA]) and were evaluated for pharmacokinetics and safety. RESULTS: A total of 29 participants (5 with severe renal impairment; 8 each with moderate and mild impairment and normal renal function) were enrolled and received a single dose of lorlatinib 100 mg. One of the participants with severe renal impairment had end-stage renal disease with a baseline absolute eGFR of 10.3 mL/min. No serious adverse events (AEs) were reported. Eighteen AEs, all mild or moderate in severity, were reported by 12 participants (5, 2, 4, and 1 in the normal, mild, moderate, and severe groups, respectively). Area under the plasma concentration-time profile from time zero extrapolated to infinity (AUCinf) for lorlatinib was increased by 4%, 19%, and 41% in the mild, moderate, and severe renal impairment groups, respectively, compared with the normal renal function cohort. CONCLUSION: Lorlatinib 100 mg was well tolerated. As participants with mild and moderate renal impairment did not experience clinically meaningful increases in lorlatinib exposure, no lorlatinib dose adjustment is recommended in these populations. Patients with severe renal impairment are recommended to reduce the starting dose of lorlatinib from 100 mg QD to 75 mg QD. GOV IDENTIFIER: NCT03542305 (available May 31, 2018 on clinicaltrials.gov).

Evaluation of the absolute oral bioavailability of the anaplastic lymphoma kinase/c-ROS oncogene 1 kinase inhibitor lorlatinib in healthy participants.

PURPOSE: Lorlatinib is a third-generation tyrosine kinase inhibitor currently approved for the treatment of anaplastic lymphoma kinase (ALK)-positive metastatic non-small cell lung cancer. This open-label, phase 1, randomized two-sequence, two-treatment, two-period, crossover study investigated the absolute oral bioavailability of lorlatinib in healthy participants. METHODS: Eligible participants were randomized to receive two treatments in one of two sequences: lorlatinib 100 mg single oral dose followed by lorlatinib 50 mg intravenous (IV) dose, or lorlatinib IV dose followed by lorlatinib oral dose, each with at least a 10-day washout between successive lorlatinib doses. Blood samples for pharmacokinetics were collected for up to 144 hours (h) after dosing. Validated liquid chromatographic-tandem mass spectrometry was used to determine plasma concentrations of lorlatinib and its benzoic acid metabolite PF-06895751. RESULTS: In total, 11 participants were enrolled (mean age 37.6 years, all male). The adjusted geometric mean (90% confidence interval) for the absolute oral bioavailability was 80.78% (75.73-86.16%). Using non-compartmental analysis, the estimated arithmetic mean elimination plasma half-life of lorlatinib was 25.5 and 27.0 h after the oral and IV doses, respectively. No deaths, serious adverse events (AEs), or severe AEs were reported, and most treatment-emergent AEs were mild in severity, with two events of transaminase increase of moderate severity. All treatment-emergent AEs were resolved by the end of the study. CONCLUSION: Both oral and IV lorlatinib were well-tolerated in healthy participants and oral lorlatinib is highly bioavailable after oral administration.

An oral SARS-CoV-2 Mpro inhibitor clinical candidate for the treatment of COVID-19.

The worldwide outbreak of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic. Alongside vaccines, antiviral therapeutics are an important part of the healthcare response to countering the ongoing threat presented by COVID-19. Here, we report the discovery and characterization of PF-07321332, an orally bioavailable SARS-CoV-2 main protease inhibitor with in vitro pan-human coronavirus antiviral activity and excellent off-target selectivity and in vivo safety profiles. PF-07321332 has demonstrated oral activity in a mouse-adapted SARS-CoV-2 model and has achieved oral plasma concentrations exceeding the in vitro antiviral cell potency in a phase 1 clinical trial in healthy human participants.

Phase 1 Study Evaluating the Effects of the Proton Pump Inhibitor Rabeprazole and Food on the Pharmacokinetics of Lorlatinib in Healthy Participants.

Lorlatinib is approved worldwide as treatment for anaplastic lymphoma kinase-positive and c-ros oncogene 1-positive non-small cell lung cancer. The objectives of this phase 1, open-label crossover study (NCT02569554) in healthy adult participants were to determine (1) the effects of the proton pump inhibitor (PPI) rabeprazole on lorlatinib pharmacokinetics (PK), (2) the effects of a high-fat meal on lorlatinib PK, and (3) the relative bioavailability of an oral solution to tablet formulation of lorlatinib under fasted conditions. Participants were followed on-study for ≥50 days after the first dose of lorlatinib. Participants received treatments over 4 periods, with a washout of ≥10 days between consecutive lorlatinib doses. Twenty-seven participants were enrolled and received lorlatinib, and all were assessed for PK and safety. Results showed no effect of multiple doses of rabeprazole on the total plasma exposure of a single oral dose of lorlatinib 100-mg tablets. The results also indicated that a high-fat meal had no effect on lorlatinib PK after a single 100-mg oral dose. In addition, the relative bioavailability of lorlatinib oral solution compared with lorlatinib tablets was complete (approximately 108%). The safety profile of lorlatinib was consistent with that reported in previous studies, and most treatment-related adverse events were mild to moderate. These data indicate that lorlatinib can be administered with drugs that modify gastric acid, including PPIs, without restriction. These results also confirm that lorlatinib can be administered regardless of food intake.

Lorlatinib Exposure-Response Analyses for Safety and Efficacy in a Phase I/II Trial to Support Benefit-Risk Assessment in Non-Small Cell Lung Cancer.

Lorlatinib is a small molecule inhibitor of anaplastic lymphoma kinase (ALK) and c-ROS oncogene 1 (ROS1) tyrosine kinases and is approved for the treatment of patients with ALK-positive advanced non-small cell lung cancer (NSCLC). In the phase I/II study (NCT01970865), potential exposure-response (E-R) relationships between lorlatinib and selected safety and efficacy end points were evaluated in patients with NSCLC. E-R relationships were assessed for safety end points with incidence > 10% in all treated patients (n = 328). In total, 4 safety end points were assessed: hypercholesterolemia grade ≥ 3, hypertriglyceridemia grade ≥ 3, weight gain grade ≥ 2, and treatment-emergent adverse events (TEAEs) grade ≥ 3. Using logistic regression, significant relationships were identified between lorlatinib plasma exposure and risk of hypercholesterolemia grade ≥ 3 (odds ratio (OR) 5.256) and risk of TEAE grade ≥ 3 (OR 3.214). The covariates baseline cholesterol and time on study prior to the event (TE) were associated with the probability of hypercholesterolemia grade ≥ 3. Baseline cholesterol and TE were found to have a statistically significant correlation with TEAE grade ≥ 3. Exposure-efficacy relationships were assessed for objective response rate (ORR; n = 197) and intracranial objective response rate (IC-ORR; n = 132). Lorlatinib plasma exposure was not identified as a statistically significant factor related to either efficacy end point. The only significant E-R relationships identified for efficacy were between baseline alkaline phosphatase and baseline amylase with IC-ORR (ORs 0.363 and 1.015, respectively). These findings support the lorlatinib indicated dose and dose modification guidelines regarding the management of lorlatinib-related AEs.

Population pharmacokinetic model with time-varying clearance for lorlatinib using pooled data from patients with non-small cell lung cancer and healthy participants.

Lorlatinib, a selective inhibitor of anaplastic lymphoma kinase (ALK) and c-ROS oncogene 1 (ROS1) tyrosine kinase, is indicated for the treatment of ALK-positive metastatic non-small cell lung cancer (NSCLC) following progression on crizotinib and at least one other ALK inhibitor, or alectinib/ceritinib as the first ALK inhibitor therapy for metastatic disease. The population pharmacokinetics (PopPK) of lorlatinib was conducted by nonlinear mixed effects modeling of data from 330 patients with ALK-positive or ROS1-positive NSCLC and 95 healthy participants from six phase I studies in healthy volunteers; demographic, metabolizer phenotype, and patient prognostic factors were evaluated as covariates. Lorlatinib plasma PK was well-characterized by a two-compartment model with sequential zero-order and first-order absorption and a time-varying induction of clearance. Single dose clearance was estimated to be 9.04 L/h. Assuming that the metabolic auto-induction of lorlatinib reaches saturation in ~ 5 half-lives, clearance was estimated to approach a maximum of 14.5 L/h at steady-state after a period of ~ 7.25 days. The volume of distribution of the central compartment was estimated to be 121 L and the first-order absorption rate constant was estimated to be 3.1 h-1 . Baseline albumin and lorlatinib total daily dose were significant covariates on lorlatinib clearance. Use of proton pump inhibitors was found to be a significant covariate on the lorlatinib absorption rate constant. These factors were assessed to have no clinically meaningful impact on lorlatinib plasma exposure, and no dose adjustments are considered necessary based on the examined covariates.

Facile preparation of a novel Ga-67-labeled NODAGA-conjugated lactam-cyclized alpha-MSH peptide at room temperature for melanoma targeting.

In this study, the melanoma targeting property of 67Ga-NODAGA-GGNle-CycMSHhex {1,4,7-triazacyclononane,1-gluteric acid-4,7-acetic acid-GlyGlyNle-c[Asp-His-D-Phe-Arg-Trp-Lys]-CONH2} was determined on B16/F10 melanoma-bearing C57 mice to demonstrate the feasibility of NODAGA as a radiometal chelator for facile room temperature radiolabeling of NODAGA-GGNle-CycMSHhex. The IC50 value of NODAGA-GGNle-CycMSHhex was 0.87 ± 0.12 nM on B16/F10 melanoma cells. 67Ga-NODAGA-GGNle-CycMSHhex was readily prepared at room temperature with greater than 98% radiolabeling yield and displayed MC1R-specific binding on B16/F10 melanoma cells. The B16/F10 melanoma uptake of 67Ga-NODAGA-GGNle-CycMSHhex was 10.31 ± 0.78, 14.96 ± 1.34, 13.7 ± 3.33 and 10.4 ± 2.2% ID/g at 0.5, 2, 4 and 24 h post-injection, respectively. Approximately 85% of the injected dose was cleared out the body via urinary system at 2 h post-injection. 67Ga-NODAGA-GGNle-CycMSHhex showed high tumor/blood, tumor/muscle and tumor/skin uptake ratios after 2 h post-injection. Overall, 67Ga-NODAGA-GGNle-CycMSHhex could be easily prepared at room temperature and exhibited favorable melanoma targeting property, suggesting the potential use of NODAGA as a radiometal chelator for facile room temperature radiolabeling of α-MSH peptides.

A γ-Lactam Siderophore Antibiotic Effective against Multidrug-Resistant Gram-Negative Bacilli.

Treatment of multidrug-resistant Gram-negative bacterial pathogens represents a critical clinical need. Here, we report a novel γ-lactam pyrazolidinone that targets penicillin-binding proteins (PBPs) and incorporates a siderophore moiety to facilitate uptake into the periplasm. The MIC values of γ-lactam YU253434, 1, are reported along with the finding that 1 is resistant to hydrolysis by all four classes of ß-lactamases. The druglike characteristics and mouse PK data are described along with the X-ray crystal structure of 1 binding to its target PBP3.

Safety and Pharmacokinetic Characterization of Nacubactam, a Novel ß-Lactamase Inhibitor, Alone and in Combination with Meropenem, in Healthy Volunteers.

Nacubactam is a novel ß-lactamase inhibitor with dual mechanisms of action as an inhibitor of serine ß-lactamases (classes A and C and some class D) and an inhibitor of penicillin binding protein 2 in Enterobacteriaceae The safety, tolerability, and pharmacokinetics of intravenous nacubactam were evaluated in single- and multiple-ascending-dose, placebo-controlled studies. Healthy participants received single ascending doses of nacubactam of 50 to 8,000 mg, multiple ascending doses of nacubactam of 1,000 to 4,000 mg every 8 h (q8h) for up to 7 days, or nacubactam of 2,000 mg plus meropenem of 2,000 mg q8h for 6 days after a 3-day lead-in period. Nacubactam was generally well tolerated, with the most frequently reported adverse events (AEs) being mild to moderate complications associated with intravenous access and headache. There was no apparent relationship between drug dose and the pattern, incidence, or severity of AEs. No clinically relevant dose-related trends were observed in laboratory safety test results. No serious AEs, dose-limiting AEs, or deaths were reported. After single or multiple doses, nacubactam pharmacokinetics appeared linear, and exposure increased in an approximately dose-proportional manner across the dose range investigated. Nacubactam was excreted largely unchanged into urine. Coadministration of nacubactam with meropenem did not significantly alter the pharmacokinetics of either drug. These findings support the continued clinical development of nacubactam and demonstrate the suitability of meropenem as a potential ß-lactam partner for nacubactam. (The studies described in this paper have been registered at ClinicalTrials.gov under NCT02134834 [single ascending dose study] and NCT02972255 [multiple ascending dose study].).

Melanoma-Targeting Property of Y-90-Labeled Lactam-Cyclized α-Melanocyte-Stimulating Hormone Peptide.

Purpose: The purpose of this study was to evaluate melanoma-targeting property of 90Y-DOTA-GGNle-CycMSHhex to facilitate its potential therapeutic application. Materials and Methods: DOTA-GGNle-CycMSHhex was synthesized and readily labeled with 90Y in 0.25 M NH4Ac-buffered solution to generate 90Y-DOTA-GGNle-CycMSHhex. The specific receptor binding, internalization, and efflux of 90Y-DOTA-GGNle-CycMSHhex were determined on B16/F10 murine melanoma cells. The biodistribution property of 90Y-DOTA-GGNle-CycMSHhex was examined on B16/F10 melanoma-bearing C57 mice. Results: 90Y-DOTA-GGNle-CycMSHhex displayed receptor-specific binding, rapid internalization, and prolonged efflux on B16/F10 melanoma cells. 90Y-DOTA-GGNle-CycMSHhex exhibited high uptake and prolonged retention in melanoma, and fast urinary clearance on B16/F10 melanoma-bearing C57 mice. The B16/F10 tumor uptake was 20.73% ± 7.99%, 19.93% ± 5.73%, 14.8% ± 4.61%, and 6.69% ± 1.85% ID/g at 0.5, 2, 4, and 24 h postinjection, respectively. Conclusions: 90Y-DOTA-GGNle-CycMSHhex displayed melanocortin-1 receptor (MC1R) targeting and specificity on B16/F10 melanoma cells and tumors. The favorable melanoma-targeting property and fast urinary clearance of 90Y-DOTA-GGNle-CycMSHhex warranted its evaluation for melanoma therapy in future studies.

Danoprevir: First Global Approval.

Ascletis has developed danoprevir (Ganovo®), an orally-administered hepatitis C virus NS3 protease inhibitor, as a treatment for hepatitis C. Based on positive results in phase II and phase III trials in patients with hepatitis C, danoprevir, in combination with ritonavir, peginterferon alfa and ribavirin was recently approved for marketing in China for the treatment of treatment-naive patients with non-cirrhotic genotype 1b chronic hepatitis C. This article summarizes the milestones in the development of danoprevir leading to this first approval.

Ribbon-like Foldamers for Cellular Uptake and Drug Delivery.

Different intracellular delivery systems of bioactive compounds have been developed, including cell-penetrating peptides. Although usually nontoxic and biocompatible, these vectors share some of the general drawbacks of peptides, notably low bioavailability and susceptibility to protease degradation, that limit their use. Herein, the conversion of short peptide sequences into poly-α-amino-γ-lactam foldamers that adopt a ribbon-like structure is investigated. This template is used to distribute critical cationic and/or hydrophobic groups on both sides of the backbone, leading to potent short, cell-permeable foldamers with a low positive-charge content. The lead compound showed dramatically improved protease resistance and was able to efficiently deliver a biologically relevant cargo inside cells. This study provided a simple strategy to convert short peptide sequences into efficient protease-resistant cell-penetrating foldamers.

Identification and Profiling of a Selective and Brain Penetrant Radioligand for in Vivo Target Occupancy Measurement of Casein Kinase 1 (CK1) Inhibitors.

To enable the clinical development of our CNS casein kinase 1 delta/epsilon (CK1δ/ε) inhibitor project, we investigated the possibility of developing a CNS positron emission tomography (PET) radioligand. For this effort, we focused our design and synthesis efforts on the initial CK1δ/ε inhibitor HTS hits with the goal of identifying a compound that would fulfill a set of recommended PET ligand criteria. We identified [3H]PF-5236216 (9) as a tool ligand that meets most of the key CNS PET attributes including high CNS MPO PET desirability score and kinase selectivity, CNS penetration, and low nonspecific binding. We further used [3H]-9 to determine the binding affinity for PF-670462, a literature CK1δ/ε inhibitor tool compound. Lastly, [3H]-9 was used to measure in vivo target occupancy (TO) of PF-670462 in mouse and correlated TO with CK1δ/ε in vivo pharmacology (circadian rhythm modulation).

Cell-Penetrating Peptide Spirolactam Derivative as a Reversible Fluorescent pH Probe for Live Cell Imaging.

A colorless and nonfluorescent spirolactam derivative, RhB-R12K, was synthesized by amide condensation between the carboxyl group of rhodamine B (RhB) and the amino group of cell-penetrating peptide (CPP). The fluorescence intensity of RhB-R12K sharply increased as the pH value decreased from 8.0 to 4.9, demonstrating sensitive and reversible response to intracellular pH distribution. This CPP probe was completely water soluble, had low cytotoxicity, was membrane permeable, and was suitable for pH measurement in various organelles by choosing organelle-specific CPP sequences. Interestingly, CPPs acted not only as carriers but also as indispensable parts of fluorophores here. The presence of active groups on the peptides potentially allows for modification with additional dyes to construct multifunctional and ratiometric probes for cell imaging.

The anti-dementia drug candidate, (-)-clausenamide, improves memory impairment through its multi-target effect.

Multi-target drugs, such as the cocktail therapy used for treating AIDS, often show stronger efficacy than single-target drugs in treating complicated diseases. This review will focus on clausenamide (clau), a small molecule compound originally isolated from the traditional Chinese herbal medicine, Clausenalansium. The finding of four chiral centers in clau molecules predicted the presence of 16 clau enantiomers, including (-)-clau and (+)-clau. All of the predicted enantiomers have been successfully synthesized via innovative chemical approaches, and pharmacological studies have demonstrated (-)-clau as a eutomer and (+)-clau as a distomer in improving cognitive function in both normal physiological and pathological conditions. Mechanistically, the nootropic effect of (-)-clau is mediated by its multi-target actions, which include mild elevation of intracellular Ca(2+) concentrations, modulation of the cholinergic system, regulation of synaptic plasticity, and activation of cellular and molecular signaling pathways involved in learning and memory. Furthermore, (-)-clau suppresses the pathogenesis of Alzheimer's disease by inhibiting multiple etiological processes: (1) beta amyloid protein-induced intracellular Ca(2+) overload and apoptosis and (2) tau hyperphosphorylation and neurodegeneration. In conclusion, the nature of the multi-target actions of (-)-clau substantiates it as a promising chiral drug candidate for enhancing human cognition in normal conditions and treating memory impairment in neurodegenerative diseases.

Modelling the interaction between danoprevir and mericitabine in the treatment of chronic HCV infection.

BACKGROUND: Modelling HCV RNA decline kinetics under therapy has proven useful for characterizing treatment effectiveness. METHODS: Here we model HCV viral kinetics (VK) in 72 patients given a combination of danoprevir, a protease inhibitor, and mericitabine, a nucleoside polymerase inhibitor, for 14 days in the INFORM-1 trial. A biphasic VK model with time-varying danoprevir and mericitabine effectiveness and Bliss independence for characterizing the interaction between both drugs provided the best fit to the VK data. RESULTS: The average final antiviral effectiveness of the drug combination varied between 0.998 for 100 mg three times daily of danoprevir and 500 mg twice daily of mericitabine and 0.9998 for 600 mg twice daily of danoprevir and 1,000 mg twice daily of mericitabine. Using the individual parameters estimated from the VK data collected over 2 weeks, we were not able to reproduce the low sustained virological response rates obtained in a more recent study where patients were treated with a combination of mericitabine and ritonavir-boosted danoprevir for 24 weeks. CONCLUSIONS: This suggests that drug-resistant viruses emerge after 2 weeks of treatment and that longer studies are necessary to provide accurate predictions of longer treatment outcomes.