A Prescription Digital Therapeutic to Support Unsupervised Buprenorphine Initiation for Patients With Opioid Use Disorder: Protocol for a Proof-of-Concept Study.

BACKGROUND: Home-based (unsupervised) buprenorphine initiation is considered safe and effective, yet many patients report barriers to successful treatment initiation. Prescription digital therapeutics (PDTs) are software-based disease treatments regulated by the US Food and Drug Administration (FDA). The reSET-O PDT was authorized by the FDA in 2018 and delivers behavioral treatment for individuals receiving buprenorphine for opioid use disorder (OUD). A prototype PDT (PEAR-002b) designed for use with reSET-O was developed to assist in unsupervised buprenorphine initiation. OBJECTIVE: The primary objective of this pilot study is to evaluate the acceptability of PEAR-002b in individuals with OUD who use it to support buprenorphine initiation, their unsupervised buprenorphine initiation success rate, and their medication adherence. METHODS: Ten adults with OUD will be recruited for acceptability and feasibility testing. Outcomes will be assessed using week-1 visit attendance, participant interviews and satisfaction surveys, and urine drug screening (UDS). Three tools will be used in the study: PEAR-002b, reSET-O, and EmbracePlus. PEAR-002b includes a new set of features designed for use with reSET-O. The mechanism of action for the combined PEAR-002b and reSET-O treatment is a program of medication dosing support during week 1 of the initiation phase, cognitive behavioral therapy, and contingency management. During the medication initiation phase, participants are guided through a process to support proper medication use. PEAR-002b advises them when to take their buprenorphine based on provider inputs (eg, starting dose), self-reported substance use, and self-reported withdrawal symptoms. This study also administers the EmbracePlus device, a medical-grade smartwatch, to pilot methods for collecting physiologic data (eg, heart rate and skin conductance) and evaluate the device's potential for use along with PDTs that are designed to improve OUD treatment initiation. Home buprenorphine initiation success will be summarized as the proportion of participants attending the post-buprenorphine initiation visit (week 1) and the proportion of participants who experience buprenorphine initiation-related adverse events (eg, precipitated withdrawal). Acceptability of PEAR-002b will be evaluated based on individual participants' ratings of ease of use, satisfaction, perceived helpfulness, and likelihood of recommending PEAR-002b. Medication adherence will be evaluated by participant self-report data and confirmed by UDS. UDS data will be summarized as the mean of individual participants' proportion of total urine samples testing positive for buprenorphine or norbuprenorphine over the 4-week study. RESULTS: This project was funded in September 2019. As of September 2022, participant enrollment is ongoing. CONCLUSIONS: This is the first study to our knowledge to develop a PDT that assists with unsupervised buprenorphine initiation with the intent to better support patients and prescribers during this early phase of treatment. This pilot study will assess the acceptability and utility of a digital therapeutic to assist individuals with OUD with unsupervised buprenorphine initiation. TRIAL REGISTRATION: ClinicalTrials.gov NCT05412966; https://clinicaltrials.gov/ct2/show/NCT05412966. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/43122.

Evaluation of real-world outcomes associated with use of a prescription digital therapeutic to treat substance use disorders.

BACKGROUND AND OBJECTIVES: Digital therapeutics can expand the reach and fidelity of behavioral treatment for substance use disorders (SUDs). This analysis evaluated real-world engagement and clinical outcomes in patients diagnosed with SUD who were prescribed reSET®, an FDA-authorized prescription digital therapeutic (PDT). METHODS: Patients were prescribed a 12-week PDT comprising 61 therapy lessons (31 "core" and 30 "keep learning" lessons) and contingency management rewards (positive reinforcement message or monetary gift cards) based on lesson completion and negative urine drug screens. Engagement (defined as any activity in the PDT), retention (any activity in Weeks 9-12), and substance use data were collected automatically by the PDT and analyzed descriptively. Associations between early lesson completion and end-of-treatment outcomes were assessed. RESULTS: Six hundred and fifty-eight patients filled their prescription. Evaluated were 602 patients who were exposed to therapeutic content by completing at least one lesson (median age 37 years, 33% female, 41% male, 26% unreported sex). Median lessons completed was 33 (out of 61 possible), and 52% of patients completed all core modules. Retention in treatment during the last 4 weeks of treatment was 74%, and 62% were abstinent (missing data considered positive). [Correction added on 13 December 2022, after first online publication: In the preceding sentence, the treatment percentage values were revised from 74.6% to 74%.] DISCUSSION AND CONCLUSIONS: Patients with SUD exhibited robust engagement with a PDT, high rates of retention through 12 weeks, and substantial rates of abstinence at end of treatment when the therapeutic was used in a real-world setting. PDT's hold promise as a new way to access effective SUD treatment. SCIENTIFIC SIGNIFICANCE: This study is the first to report real-world PDT engagement and clinical outcomes data from a large, geographically diverse population of patients with SUDs.

Real-World Evaluation of Clinical Response and Long-Term Healthcare Resource Utilization Patterns Following Treatment with a Digital Therapeutic for Chronic Insomnia.

Background and Objectives: This analysis evaluated insomnia severity and long-term impact on healthcare resource utilization (HCRU) and costs after treatment with Somryst® (previously called SHUTi), a digital therapeutic delivering cognitive behavioral therapy for insomnia (CBT-I). Methods: Change from baseline in insomnia severity index (ISI) score was assessed using last observed ISI score. A pre/post analysis of claims data was conducted, comparing HCRU in patients with self-identified sleep problems who successfully initiated the therapeutic (index date) between June 1, 2016 and December 31, 2018. Results: A total of 248 patients were analyzed (median age 56.5 years, 57.3% female, mean ISI score 19.13, 52.4% treated with sleep aid medications pre-index). After 9 weeks, mean ISI score declined by 37.2% from baseline (19.1 vs 12.0), 58.8% of patients achieved ISI responder status (ISI score improved by =>7; NNT: 1.7), and 26.6% of patients achieved insomnia remission (ISI score <8; NNT for remission: 3.8). After two-year follow-up, post-index events were reduced (compared to 2 years pre-index) for emergency department visits (-53%; IRR: 0.47; 95% CI 0.27, 0.82; P=0.008), hospiatizations (-21%; IRR: 0.79; 95% CI 0.46, 1.35; P=0.389) and hospital outpatient visits (-13%; IRR: 0.87; 95% CI 0.66, 1.14; P=0.315). Slightly increased rates were observed for ambulatory surgical center visits (2%; IRR: 1.02; 95% CI 0.73, 1.44; P=0.903) and office visits (2%; IRR: 1.02; 95% CI 0.92, 1.14; P=0.672). The number of patients treated with sleep aid medications dropped 18.5% (52.4% pre-index vs 42.7% post-index). Average number of prescriptions decreased from 3.98 pre-index to 3.73 post-index (P= 0.552). Total two-year cost reduction post-index vs pre-index was $510,678, or -$2059 per patient. Conclusion: In a real-world cohort of patients with chronic insomnia, treatment with a digital therapeutic delivering CBT-I was associated with reductions in insomnia severity, emergency department visits, and net costs.

Patient Engagement With a Game-Based Digital Therapeutic for the Treatment of Opioid Use Disorder: Protocol for a Randomized Controlled Open-Label, Decentralized Trial.

BACKGROUND: Prescription digital therapeutics are software-based disease treatments that are regulated by the US Food and Drug Administration; the reSET-O prescription digital therapeutic was authorized in 2018 and delivers behavioral treatment for individuals receiving buprenorphine for opioid use disorder. Although reSET-O improves outcomes for individuals with opioid use disorder, most of the therapeutic content is delivered as narrative text. PEAR-008 is an investigational device based on reSET-O that uses an interactive, game-based platform to deliver similar therapeutic content designed to enhance patient engagement, which may further improve treatment outcomes. OBJECTIVE: We aim to investigate how participants interact with the prescription digital therapeutic's new content delivery format. Secondary objectives include evaluating treatment success, symptoms of co-occurring mental health disorders, recovery capital, and skill development. METHODS: Due to the COVID-19 pandemic, this study was redesigned using a decentralized model because it was not possible to conduct medication initiation and study visits in person, as initially intended. A decentralized, randomized controlled trial design will be utilized to compare patient engagement with PEAR-008 and that with reSET-O using both subjective and objective assessments. The study population will consist of approximately 130 individuals with opioid use disorder (based on Diagnostic and Statistical Manual of Mental Disorders 5 criteria) who have recently started buprenorphine treatment for opioid use disorder. Participants will be virtually recruited and randomly assigned to receive either PEAR-008 or reSET-O. All study sessions will be virtual, and the duration of the study is 12 weeks. The primary outcome measure of engagement is operationalized as the number of active sessions per week with either PEAR-008 or reSET-O. (An active session is any session that contains some active participation in the app, such as navigating to a different screen, engaging with a learning module, or responding to a notification.) Subjective dimensions of engagement will be assessed with participant surveys. The hypothesis is that PEAR-008 will have significantly greater participant engagement than reSET-O. RESULTS: As of February 2021, participant enrollment is ongoing. CONCLUSIONS: This randomized controlled trial will investigate if changing the delivery format and enhancing the content of a prescription digital therapeutic for opioid use disorder will affect how participants use and interact with the prescription digital therapeutic. The study design may serve as a useful model for conducting decentralized studies in this patient population. TRIAL REGISTRATION: ClinicalTrials.gov NCT04542642; https://clinicaltrials.gov/ct2/show/NCT04542642. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/32759.

Engagement patterns with a digital therapeutic for substance use disorders: Correlations with abstinence outcomes.

INTRODUCTION: Patient engagement may play a key role in the success or failure of treatments for substance use disorder (SUD). This exploratory analysis of data from a large, multisite effectiveness trial (NCT01104805) sought to determine how patient engagement with a digital therapeutic for SUD delivered at clinics was associated with abstinence outcomes. METHODS: The study evaluated engagement for 206 participants enrolled in a treatment program for SUDs related to cocaine, alcohol, cannabis, or other stimulants who were randomized to receive treatment as usual (TAU) or reduced TAU plus the digital Therapeutic Education System (TES) for 12 weeks. Participants were eligible for contingency management incentives for module completion (modules cover Community Reinforcement Approach topic areas) and negative urine drug screens. Analyses examined the association of module completion with end-of-treatment abstinence. RESULTS: Participants completed a mean of 38.8 (range 0-72) TES modules over 12 weeks of treatment. Study completers (n = 157) completed a mean of 45.5 (range 9-72) TES modules, whereas study noncompleters (n = 49) completed a mean of 17.4 (range 0-45) TES modules. The study observed a strong positive correlation between TES engagement (i.e., total number of modules completed) and the probability of abstinence during weeks 9-12 of treatment among 157 study completers (OR = 1.11; 95% CI 1.08-1.14). Each module completed increased the odds of abstinence during weeks 9-12 by approximately 11% for study completers and 9% for the full sample. The study observed a similar, but weaker, association between engagement and abstinence among 49 patients who did not complete the study (OR = 1.02; 95% CI 0.98-1.07). CONCLUSIONS: Greater engagement with a digital therapeutic for patients with SUD (i.e., number of modules completed over time) was strongly associated with the probability of abstinence in the last four weeks of treatment among those who completed the recommended 12-week treatment. TRIALS REGISTRATION: ClinicalTrials.gov Identifier: NCT01104805.

Real-world evidence for a prescription digital therapeutic to treat opioid use disorder.

OBJECTIVES: To evaluate patient engagement and usage of a prescription digital therapeutic (PDT) and associated outcomes of opioid use and treatment retention in a large real-world dataset of patients with opioid use disorder (OUD) treated with buprenorphine medication for opioid use disorder (MOUD). PDTs are software-based disease treatments evaluated for safety and effectiveness in randomized clinical trials (RCTs), and authorized by the U.S. Food and Drug Administration (FDA) to treat disease with approved directions for use (label). METHODS: A real-world observational evaluation of an all-comer population of patients who redeemed a 12-week prescription for the reSET-O PDT. Engagement and therapeutic use data were collected and analysed on a population level. Substance use was evaluated as a composite of self-reports recorded with reSET-O and urine drug screens (UDS). RESULTS: Data from 3144 individuals with OUD were evaluated. 45.5% were between ages 30 and 39 years. 80% completed at least 8 of the 67 possible therapeutic modules, 66% completed half of all modules, and 49% completed all modules. Abstinence during the last 4 weeks of treatment was calculated with two imputation methodologies: 66% abstinent using "missing data excluded (patients with no data as positive)", and 91% abstinent with "missing data removed (patients with no data excluded)". 91% of patients met the responder definition of ≥80% of self-report or UDS negative. 74.2% of patients were retained through the last 4 weeks of treatment. Subgroup analysis of patients using reSET-O appropriately (4 or more modules per week for the first 4 weeks) showed 88.1% abstinence using "missing data excluded (patients with no data as positive)", and retention at weeks 9-12 of 85.8%. CONCLUSIONS: Results demonstrate that reSET-O is readily and broadly used by patients with OUD and that high real-world engagement with the therapeutic is positively associated with abstinence and retention in treatment. ReSET-O is a potentially valuable adjunct to buprenorphine MOUD therapy for patients with OUD.

Genetic Control of Collective Behavior in Zebrafish.

Many animals, including humans, have evolved to live and move in groups. In humans, disrupted social interactions are a fundamental feature of many psychiatric disorders. However, we know little about how genes regulate social behavior. Zebrafish may serve as a powerful model to explore this question. By comparing the behavior of wild-type fish with 90 mutant lines, we show that mutations of genes associated with human psychiatric disorders can alter the collective behavior of adult zebrafish. We identify three categories of behavioral variation across mutants: "scattered," in which fish show reduced cohesion; "coordinated," in which fish swim more in aligned schools; and "huddled," in which fish form dense but disordered groups. Changes in individual interaction rules can explain these differences. This work demonstrates how emergent patterns in animal groups can be altered by genetic changes in individuals and establishes a framework for understanding the fundamentals of social information processing.

Auditory cortex controls sound-driven innate defense behaviour through corticofugal projections to inferior colliculus.

Defense against environmental threats is essential for animal survival. However, the neural circuits responsible for transforming unconditioned sensory stimuli and generating defensive behaviours remain largely unclear. Here, we show that corticofugal neurons in the auditory cortex (ACx) targeting the inferior colliculus (IC) mediate an innate, sound-induced flight behaviour. Optogenetic activation of these neurons, or their projection terminals in the IC, is sufficient for initiating flight responses, while the inhibition of these projections reduces sound-induced flight responses. Corticocollicular axons monosynaptically innervate neurons in the cortex of the IC (ICx), and optogenetic activation of the projections from the ICx to the dorsal periaqueductal gray is sufficient for provoking flight behaviours. Our results suggest that ACx can both amplify innate acoustic-motor responses and directly drive flight behaviours in the absence of sound input through corticocollicular projections to ICx. Such corticofugal control may be a general feature of innate defense circuits across sensory modalities.

Sensory Cortical Control of a Visually Induced Arrest Behavior via Corticotectal Projections.

Innate defense behaviors (IDBs) evoked by threatening sensory stimuli are essential for animal survival. Although subcortical circuits are implicated in IDBs, it remains largely unclear whether sensory cortex modulates IDBs and what the underlying neural pathways are. Here, we show that optogenetic silencing of corticotectal projections from layer 5 (L5) of the mouse primary visual cortex (V1) to the superior colliculus (SC) significantly reduces an SC-dependent innate behavior (i.e., temporary suspension of locomotion upon a sudden flash of light as short as milliseconds). Surprisingly, optogenetic activation of SC-projecting neurons in V1 or their axon terminals in SC sufficiently elicits the behavior, in contrast to other major L5 corticofugal projections. Thus, via the same corticofugal projection, visual cortex not only modulates the light-induced arrest behavior, but also can directly drive the behavior. Our results suggest that sensory cortex may play a previously unrecognized role in the top-down initiation of sensory-motor behaviors.

Differential Receptive Field Properties of Parvalbumin and Somatostatin Inhibitory Neurons in Mouse Auditory Cortex.

Cortical inhibitory circuits play important roles in shaping sensory processing. In auditory cortex, however, functional properties of genetically identified inhibitory neurons are poorly characterized. By two-photon imaging-guided recordings, we specifically targeted 2 major types of cortical inhibitory neuron, parvalbumin (PV) and somatostatin (SOM) expressing neurons, in superficial layers of mouse auditory cortex. We found that PV cells exhibited broader tonal receptive fields with lower intensity thresholds and stronger tone-evoked spike responses compared with SOM neurons. The latter exhibited similar frequency selectivity as excitatory neurons. The broader/weaker frequency tuning of PV neurons was attributed to a broader range of synaptic inputs and stronger subthreshold responses elicited, which resulted in a higher efficiency in the conversion of input to output. In addition, onsets of both the input and spike responses of SOM neurons were significantly delayed compared with PV and excitatory cells. Our results suggest that PV and SOM neurons engage in auditory cortical circuits in different manners: while PV neurons may provide broadly tuned feedforward inhibition for a rapid control of ascending inputs to excitatory neurons, the delayed and more selective inhibition from SOM neurons may provide a specific modulation of feedback inputs on their distal dendrites.

Scaling down of balanced excitation and inhibition by active behavioral states in auditory cortex.

Cortical sensory processing is modulated by behavioral and cognitive states. How this modulation is achieved by changing synaptic circuits remains largely unknown. In awake mouse auditory cortex, we found that sensory-evoked spike responses of layer 2/3 (L2/3) excitatory cells were scaled down with preserved sensory tuning when mice transitioned from quiescence to active behaviors, including locomotion, whereas L4 and thalamic responses were unchanged. Whole-cell voltage-clamp recordings revealed that tone-evoked synaptic excitation and inhibition exhibited a robust functional balance. The change to active states caused scaling down of excitation and inhibition at approximately equal levels in L2/3 cells, but resulted in no synaptic changes in L4 cells. This lamina-specific gain control could be attributed to an enhancement of L1-mediated inhibitory tone, with L2/3 parvalbumin inhibitory neurons also being suppressed. Thus, L2/3 circuits can adjust the salience of output in accordance with momentary behavioral demands while maintaining the sensitivity and quality of sensory processing.

Interaural level difference-dependent gain control and synaptic scaling underlying binaural computation.

Binaural integration in the central nucleus of inferior colliculus (ICC) plays a critical role in sound localization. However, its arithmetic nature and underlying synaptic mechanisms remain unclear. Here, we showed in mouse ICC neurons that the contralateral dominance is created by a "push-pull"-like mechanism, with contralaterally dominant excitation and more bilaterally balanced inhibition. Importantly, binaural spiking response is generated apparently from an ipsilaterally mediated scaling of contralateral response, leaving frequency tuning unchanged. This scaling effect is attributed to a divisive attenuation of contralaterally evoked synaptic excitation onto ICC neurons with their inhibition largely unaffected. Thus, a gain control mediates the linear transformation from monaural to binaural spike responses. The gain value is modulated by interaural level difference (ILD) primarily through scaling excitation to different levels. The ILD-dependent synaptic scaling and gain adjustment allow ICC neurons to dynamically encode interaural sound localization cues while maintaining an invariant representation of other independent sound attributes.