Long‐Acting Injectable Buprenorphine in Prison: Insights From a Short‐Answer Survey of People in the Criminal Justice System Commencing Long‐Acting Injectable Buprenorphine During a Non‐Randomised Clinical Trial

ABSTRACT

Introduction

Long‐acting injectable buprenorphine (LAIB) is increasingly used in the Criminal Justice System (CJS) for treating people with opioid use disorder; however, little is known about these patients' experiences. We aimed to understand the perspectives of participants commenced on LAIB in prison as a part of the Understanding NSW Long‐Active Opioids in Custody‐Treatment (UNLOC‐T) study.

Methods

Results of an open‐ended survey administered by UNLOC‐T researchers underwent analysis. Participants were adults, recruited November 2018–July 2019, with moderate–severe opioid use disorder and ≥ 6 months remaining on their sentence. We conducted a thematic analysis using a pragmatic, descriptive coding approach.

Results

Sixty‐seven participants were included, of which 82% were male. Five primary themes were identified that described participants' experiences and highlighted issues that can directly inform service delivery: medication effectiveness, social and relational considerations, dosing frequency, financial aspects, and health and wellbeing. There was considerable variation in participant perspectives within themes.

Discussion and Conclusions

Perspectives on LAIB are diverse, suggesting a need to individualise treatment and ensure person‐centered care. While LAIB offers benefits to warrant including it as a treatment option, challenges remain. Future research into LAIB in the CJS would allow for triangulation, as well as further exploration of ongoing acceptability in the post‐release period. Our findings could help to improve the way LAIB is offered as a treatment option or delivered to people in the CJS. There are also lessons for prescribers in counselling and tailoring treatment, and broader policy considerations around access to treatment formulations and patient autonomy.

1. Introduction

People with opioid use disorder (OUD) often encounter the Criminal Justice System (CJS), with one Australian study showing 37% experience incarceration at least once within a two‐year period [1]. The CJS can serve as a vital point of healthcare contact for this population who may otherwise infrequently seek medical care [2]. Opioid agonist treatment (OAT), including buprenorphine and methadone, provides a longer and more stable duration of action than shorter‐acting opioids like heroin. However, traditional oral OAT requires frequent (often daily or second‐daily) dosing. This presents challenges within the CJS due to resource limitations and medication diversion risks and often results in under‐treatment of OUD [3].

Long‐acting injectable buprenorphine (LAIB) formulations, Buvidal and Sublocade, were introduced in Australia in 2019 and 2020 respectively [4]. LAIB has many potential advantages over shorter‐acting OAT, including improved accessibility, adherence, safety and economic benefits [5]. During COVID‐19, LAIB prescribing surged in both the general population [6] and some CJS settings [7, 8]. While studies on LAIB in general populations have identified barriers to use for some patients, including perceptions of reduced medication efficacy and duration and reduced social interactions [9, 10, 11, 12, 13, 14], research on its application within the CJS remains scant [5]. Two US studies have addressed the qualitative perspectives of treatment in the CJS with recently released participants [15, 16], but neither included currently incarcerated participants. To address this evidence gap, we aimed to explore perspectives on LAIB within the CJS, including comparisons to short‐acting formulations of OAT.

2. Methods

2.1. Ethics

The Understanding NSW Long‐Acting Opioids in Custody‐Treatment (UNLOC‐T) study was approved by the Justice Health and Forensic Mental Health Network; the Aboriginal Health and Medical Research Council Human Research Ethics Committees (Protocol JH File no. G561/17 and HREC/18/JH/3), and the Corrective Services NSW. Voluntary, written and informed consent was obtained. Results from the study were not provided directly to the study population due to feasibility issues.

2.2. Study Design

We analysed open‐ended responses from face‐to‐face surveys collected during the UNLOC‐T study. The UNLOC‐T study was conducted in 2018–2019 following registration of CAM‐2038 (a formulation of LAIB, since renamed Buvidal), and therefore reflects early experiences with one formulation of LAIB. Detailed information about UNLOC‐T methodology and other findings has been published elsewhere [17, 18, 19, 20], and a summary is provided in Appendix A.

2.3. Participants

Participants commenced on LAIB as a part of the UNLOC‐T trial were asked to complete the surveys. Inclusion criteria for UNLOC‐T trial were: ≥ 18 years old, currently in custody with a full‐time sentence of > 6 months and moderate–severe OUD (Diagnostic and Statistical Manual of Mental Disorders, 5th Edition) [21]. Participants not prescribed OAT at the time were eligible for the LAIB arm (including people who used non‐prescribed sublingual buprenorphine [SL‐BUP]). Age, gender, Indigenous status and level of education were documented.

2.4. Data Collection

Surveys were administered face‐to‐face by trained researchers in custodial health clinics at baseline (day 1, immediately following the first weekly injection), week 4 (immediately following the first monthly injection) and week 16 (4 weeks after the third monthly injection). An exit interview was conducted at week 48 where possible (see Table 1). Responses were collected using paper‐based questionnaires and entered into REDCap by the researchers.

TABLE 1.

Open‐ended survey questions at each time point.

#	Question	Week 4	Week 16	Exit
Q1	How does LAIB compare to sublingual buprenorphine (Suboxone)?	Y	Y	Y
Q2	Would you like to remain on LAIB while in prison?	~	Y	Y
Q3	Thinking about all the challenges you face when being released from prison, do you think your leaving custody on LAIB may change your experience of the first few weeks in the community?	~	Y	Y
Q4	Any disadvantages? (of being on depot on release)	~	Y	Y

Abbreviation: LAIB, long‐acting injectable buprenorphine.

2.5. Data Analysis

Demographic characteristics of our sample are reported descriptively (Table 2). Survey responses were entered into NVivo [22] and the thematic coding taxonomy was developed inductively using a pragmatic, descriptive coding strategy within thematic analysis [23, 24]. Following initial open coding conducted by A.W., C.F. and M.D. contributed to axial and refined coding. Interpretation differences were resolved by consensus. Co‐authors reviewed thematic outputs, provided substantive feedback, and refined the framing and presentation of findings. Responses were grouped into descriptive categories capturing recurrent patterns in reported experiences and concerns. This approach prioritised fidelity to participants' language, was appropriate to the depth and structure of the short‐answer survey data and aimed to summarise and organise participants' reported experiences for applied relevance, rather than to generate latent or theory‐driven interpretations.

TABLE 2.

Participant demographics.

Demographic variable	Subgroup	Number of participants (%)
Age, years	20–24	6 (6.8)
	25–29	15 (17)
	30–34	13 (14.8)
	35–39	12 (13.6)
	40–44	17 (19.3)
	45–49	4 (4.5)
Gender	Male	55 (82)
	Female	12 (18)
Aboriginality	Yes	28 (42)
	No	39 (58)

Qualitative analyses of open‐ended surveys have been undertaken previously [25, 26].

3. Results

3.1. Participant Characteristics

Participant demographics are presented in Table 2. Of the 67 participants at baseline, the mean age was 33 (SD 8.08, range 20–49). Not all participants were administered the short‐answer survey at each time point due to time constraints, and by week 48 only a small number remained in custody and were therefore eligible for the exit survey. The number of respondents with any corresponding response to the relevant question, no matter how brief, is shown in Table 3.

TABLE 3.

Number of responses at each survey.

Question	Number of participant responses
Week 4: How does [LAIB] compare to sublingual buprenorphine (Suboxone)?	64
Week 16: How does [LAIB] compare to sublingual buprenorphine (Suboxone)?	61
Week 16: Would you like to remain on [LAIB] while in prison?	61
Week 16: Thinking about all the challenges you face when being released from prison, do you think your leaving custody on [LAIB] may change your experience of the first few weeks in the community?	60
Week 16: Any disadvantages? (of being on [LAIB] on release)	38
Exit Interview: How does [LAIB] compared to sublingual buprenorphine (Suboxone)?	31
Exit Interview: Would you like to remain on [LAIB] while in prison?	28
Exit Interview: Thinking about all the challenges you face when being released from prison, do you think your leaving custody on [LAIB] may change your experience of the first few weeks in the community?	27
Exit Interview: Any disadvantages? (of being on [LAIB] on release)	13

Abbreviation: LAIB, long‐acting injectable buprenorphine.

3.2. Themes

We identified five emergent themes relating to the experiences of people recently initiated onto LAIB treatment in the CJS: medication effectiveness, frequency of dosing, social and relational considerations, impact on health and wellbeing, and economic factors (see Table 4).

TABLE 4.

Themes and subthemes.

Theme	Subtheme
Medication effectiveness	Varied goals of medication effect and effectiveness
	Effects over time
	Effect on substance use and injecting behaviours
	Factors influencing perceived effectiveness
Frequency of dosing	Convenience of reduced visits and dosing
	Confidence in dose and interaction between frequency of dosing and efficacy
	Routine and structure
	Flexibility in LAIB dosing frequency
Social and relational considerations	Stigma
	Privacy and empowerment
	Social circles
	Diversion
Health and wellbeing	Effects on the body
	Energy levels
	Needle considerations
	Effect on the mind and mental health
	Personal development
	Injecting practices and infectious disease
Financial and economic considerations	Employment considerations
	Less expenses

Abbreviation: LAIB, long‐acting injectable buprenorphine.

3.2.1. Medication Effectiveness

3.2.1.1. Varied Goals of Medication Effect and Understandings of Effectiveness

While some participants experienced different pharmacological effects from LAIB than SL‐BUP, others reported similar effects but interpreted them differently depending on their treatment goals. For example, some sought a reduction in withdrawal symptoms and cravings: ‘[I] was surprised how much it works. No cravings’ (41‐year‐old Male [41M], non‐Aboriginal, Week 4 [W4]) while others felt LAIB achieved ‘Exactly the same result …’ (37M, non‐Aboriginal, W4). Others, however, reported that LAIB was less effective: ‘[LAIB] just stops you from hanging [out], but [SL‐BUP] makes you not to want to use …’ (21M, non‐Aboriginal, W4). Participants also evaluated medication effectiveness in relation to their desired psychoactive experience. Some preferred how SL‐BUP was ‘… better for getting stoned …’ (37M, Aboriginal, W4), others that LAIB made them feel ‘… “normal” not stoned [in contrast to SL‐BUP] …’ (32‐year‐old Female [32F], Aboriginal, W4), and that it ‘… Doesn't knock you around like methadone’ (37M, non‐Aboriginal, Exit).

3.2.1.2. Effect Over Time

Participants highlighted the importance of the duration of effect on their treatment experience. Some found LAIB efficacious for the full intended period, though the reduced dosing frequency could take some psychological adjustment: ‘… once you get over [how] it will last a month … [you can] stop thinking about it’ (30M, Aboriginal, Exit). However, others reported that ‘[LAIB] is working, just not lasting’ (38F, Aboriginal, W4), particularly early in treatment. Some participants reported this improved after several injections, but others continued to struggle with the duration, particularly with the move to monthly injections: ‘would prefer once a week (by week 3 not holding so well)’ (43M, non‐Aboriginal, Exit).

Participants also discussed medication consistency, with some disliking LAIB's ‘… more constant feeling … no ups or downs, just heavy all the time’ (44M, Aboriginal, W4), while others liked LAIB's ‘even dosing’ (40M, non‐Aboriginal, W16). Some participants also reported preferring the ‘… immediate effect of [SL‐BUP]’ (33M, Aboriginal, W4) and feeling that ‘… the injection takes too long to kick in’ (30M, Aboriginal, W4).

3.2.1.3. Effect on Substance Use and Injecting Behaviours

From week 16 onward, participants described differing experiences of LAIB's ability to suppress substance use, with some reporting a reduction while others identified that they could ‘… still use on top …’ (28M, non‐Aboriginal, W16). While the primary aim of treatment with LAIB is its impact on opioid use and associated harms, some participants noted a reduction in other substances and associated benefits: ‘Lower ice intake … which could speed up release [from prison]’ (43M, non‐Aboriginal, W16). Participants also reflected on an improved sense of self‐efficacy: ‘I feel proud, not injecting …’ (32F, Aboriginal, W16).

3.2.1.4. Factors Influencing Perceived Effectiveness

Many participants reported experiencing or anticipating inadequate medication doses, making dose sufficiency a central concern, particularly early in treatment: ‘[LAIB] works great but access to top ups or an appropriate dose is bad’. Whereas illicit SL‐BUP was ‘easily accessible… can store it up …’ (38M, Aboriginal, W4) which allowed greater autonomy and an increased feeling of being ‘held’. It was also identified that control over cravings might shift with release: ‘Don't know if [LAIB] would hold me on the outside (more [drugs] out there)’ (38M, non‐Aboriginal, W16).

Some reports of LAIB's waning effect were framed by participants as potentially psychological: ‘Last couple of days I think it wears off. But … [it] may be just psychological’ (38M, Aboriginal, W4) and ‘… the mental factor – it's hard to go a month without using’ (33M, non‐Aboriginal, W16). A tension emerged regarding whether symptoms reflected psychological expectancy or physical withdrawal: ‘[I experienced] physical anticipation (i.e., [anticipating] the dose and [feeling] anxious). But no symptoms of withdrawal’ (45M, non‐Aboriginal, W4). Experiences and behaviours were also shaped by peers: ‘prefer [methadone] – haven't been on it [but] heard [it's] better for treating heroin addiction’ (37M, non‐Aboriginal, Exit) and ‘A few people suggested rubbing it to get more out (into blood stream)’ (29F, Aboriginal, W4), though this is not pharmacologically accurate.

3.2.2. Frequency of Dosing

3.2.2.1. Convenience of Reduced Visits and Dosing

LAIB's reduced treatment‐related visits were generally perceived as more convenient and conducive to a sense of ease and normalcy: ‘monthly is less hassle, [can] get on with life’ (43M, non‐Aboriginal, W4) and ‘don't have to come in and line up’ (49M, non‐Aboriginal, W16).

3.2.2.2. Confidence in Dose and Interaction Between Frequency of Dosing and Efficacy

Some participants preferred LAIB because it provided reassurance that the medication was active from the start of the day: ‘Wake up ready to go … [on SL‐BUP] you wake up and look for a shot [of SL‐BUP] …’ (26M, non‐Aboriginal, W4). However, a tension emerged with many respondents perceiving that SL‐BUP ‘… [holds] you better because you're getting them regularly …’ (28M, Aboriginal, W16) and is ‘reassuring that you've had something’ (25M, Aboriginal, W4). One participant highlighted the trade‐off between efficacy and convenience: ‘… [I like] the security of being held more than convenience. Decreased visits [are] okay [but] … if it means I'm being held I don't care’ (20F, Aboriginal, W16).

3.2.2.3. Routine and Structure

Participants differed in how changes to their routine under LAIB were experienced. Some developed ‘a normal routine’ (40M, Aboriginal, Exit) with the reduced dosing, while others preferred daily dosing because ‘Routine in jail is something you stick by’ (38F, Aboriginal, W4). Routine was felt to have particular benefits when released in reducing re‐offending risk.

3.2.2.4. Flexibility in LAIB Dosing Frequency

Participants also emphasised the importance of flexibility in dosing frequency, for example feeling that ‘… Monthly's are too far apart … Would have stayed on [LAIB] if weeklies were offered … felt nothing for last two [weeks]’ (25M, Aboriginal, W16).

3.2.3. Social and Relational Considerations

3.2.3.1. Stigma

Some participants noted a reduction in stigma: ‘Stigma attached to strips … [whereas LAIB] is considered more like a medical thing’ (43M, non‐Aboriginal, W4). There was specific mention of reduced stigma from prison officers: ‘Even officers treat you differently … They're not even concerned about doing [LAIB] treatment. Treat you like a junky on methadone and suboxone’ (43M, non‐Aboriginal, Exit). Internalised stigma also persisted, with one participant noting that a disadvantage of LAIB was ‘it being a drug’ (30M, Aboriginal, W16).

3.2.3.2. Privacy and Empowerment

Participants experienced LAIB as providing greater privacy. In many CJS, dosing of oral OAT often involves thorough monitoring in the presence of custodial staff to minimise risk of diversion. This process was viewed as lacking respect and trust: ‘… being interrogated and scrutinised … It's an invasion of my body and my privacy and personal space, because they constantly check your mouth etc. It's degrading, it's shaming’ (44M, Aboriginal, W16). Participants noted that with LAIB they ‘… don't have to be watched dose’ (33M, non‐Aboriginal, W16) and consequently ‘… can control who knows’ (40M, non‐Aboriginal, W16). Associated benefits included ‘Not having … the officers hassling you’ (43M, non‐Aboriginal, W4) and ‘people … leaving me alone’ (37M, Aboriginal, W16).

3.2.3.3. Social Circles

The decreased social interactions that came from the more infrequent dosing had mixed consequences for participants. For some, LAIB was beneficial for keeping them ‘out of the using circles’ (38M, Aboriginal, Exit), while others preferred SL‐BUP in the community as it ‘… provides a social outlet when presenting for dosing’ (43F, non‐Aboriginal, W4).

3.2.3.4. Diversion and Extra‐Medical Use

Participants felt ‘… lower pressure to divert’ to other inmates, and linked this to benefits such as ‘[stopping] a lot of violence in prison’ (44M, non‐Aboriginal, W4). However, one participant noted a preference for SL‐BUP because they could tailor their use and ‘… store [SL‐BUP] up…’ (38M, Aboriginal, W4).

3.2.4. Health and Wellbeing

3.2.4.1. Effects on the Body

Participants reported a range of health effects from LAIB. Some felt it was ‘better for your health’ than SL‐BUP due to fewer health issues, eg ‘tooth aches [and] headache’ (40M, non‐Aboriginal, W4) or fewer medication side effects. Others, however, reported undesirable side effects including ‘body aches’ (30M, Aboriginal, Exit) and ‘hot flushes’ (35F, Aboriginal, W4). Participants also expressed uncertainty about the long‐term health implications of the new formulation.

3.2.4.2. Energy Levels

LAIB was associated with variable effects on energy levels, with some reporting more energy and others lethargy. One participant highlighted how their treatment preferences may shift in response to both experienced effects and context: ‘[LAIB] in jail is good (but I get a bit tired). [SL‐BUP is better on the] outside … [as I] felt more energetic’ (38M, non‐Aboriginal, W16).

3.2.4.3. Needle Considerations

Some participants disliked that LAIB was only available via subcutaneous injection. Some remarked that the ‘… injection hurts’ (38M, Aboriginal, Exit), while others found injecting practices triggering: ‘Prefer oral – sticking needles isn't something I want to continue. I try to avoid that …’ (38F, Aboriginal, W4). However, others specifically commented that they were ‘not bothered that it's an injection’ (29F, Aboriginal, W4).

3.2.4.4. Effect on the Mind and Mental Health Considerations

Some participants experienced mental health benefits with LAIB: ‘… [I felt] a lot more stability, especially emotionally’ (40M, Aboriginal, W16) and ‘[LAIB has been] mellowing [me] out’ (35M, non‐Aboriginal, W4). One participant noted a ‘… more positive outlook for when you're released’ (43F, non‐Aboriginal, W16). Conversely, others described challenges in their mental health such as ‘anxiety/depression’ (35M, non‐Aboriginal, W16) and cognition such as feeling ‘real cloudy … [I] found it hard to remember’ (35M, non‐Aboriginal, W16) with LAIB.

3.2.4.5. Personal Development

Reduced dosing frequency enabled participants to pursue enriching activities: ‘I can start focusing on other things now i.e., my health and fitness, reading and writing’ (37M, Aboriginal, W16) and ‘… only have to pick up once a month. A chance to work on me … An experience that … changed my life.’ (40M, Aboriginal, Exit).

3.2.4.6. Injecting Practices and Infectious Disease

Participants reported that LAIB reduced non‐medical injecting and improved health outcomes: ‘[a benefit is] not catching Hep C/HIV’ (29F, Aboriginal, W16).

3.2.5. Financial and Economic Considerations

3.2.5.1. Employment Considerations

While LAIB was provided free for participants during the trial, many participants raised other economic considerations relevant to treatment. Some highlighted improved employment flexibility: ‘You can go away for work’ (44M, non‐Aboriginal, Exit), which could be particularly beneficial in the community. However, others expressed how OAT broadly can have negative effects on employability: ‘Limits jobs due to officers not wanting to hire people on [OAT]’ (43M, non‐Aboriginal, W16).

3.2.5.2. Less Expenses

Participants experienced greater financial stability due to being able to ‘save money’ (multiple participants, W16) and to reduce drug‐related offending: ‘Prior to [LAIB I was] having to sell drugs to support my habit’ (43M, non‐Aboriginal, Exit) and ‘Financial incentive to divert will drop’ (44M, non‐Aboriginal, W4).

4. Discussion

We reported on the experiences of treatment with LAIB in a CJS cohort, identifying five themes: medication effectiveness, frequency of dosing, social and relational considerations, health and wellbeing, and economic aspects. LAIB offered several treatment advantages, yet many participants also expressed reservations indicating that individualised, person‐centred treatment, sensitive to these experiences, might be more appropriate than a one‐size‐fits‐all model. Participants' experiences also appeared to shift over time and across settings, particularly in relation to perceived medication effects over time, substance use and factors influencing effectiveness. The diversity in perspectives is consistent with the broader literature, both within CJS [15, 16] and general population studies [9, 11, 12], where LAIB is similarly experienced as offering both benefits and drawbacks [13]. This likely reflects the complex interplay of individual preference, pharmacology, temporality and broader sociocultural factors such as LAIB's novelty, stigma, OAT provision procedures and drug policies [9]. It is an important finding for CJSs, where service constraints such as funding and staffing may result in uniform approaches. This approach risks misaligning treatment and patient preferences, which may result in poorer treatment outcomes.

4.1. Medication Effectiveness

Our findings show that participants' goals for OAT, and therefore their views of ‘effectiveness’, can differ. This likely reflects the many factors shaping treatment perceptions, including dose, treatment duration, prior experiences, understandings of withdrawal and broader context [27, 28, 29]. The variation is consistent with both general population [30] and CJS literature [15, 16]. For example, Cheng et al. [15] highlighted the importance of adequate dosing to reduce withdrawal on release and subsequent re‐offending, an issue that was not raised in our incarcerated sample. This demonstrates how treatment priorities shift over time and settings, and should be factored into treatment decisions. Future research could explore more explicitly how substance use histories, treatment factors and context influence LAIB expectations and experiences.

Participants also described effectiveness in terms of how immediate and sustained LAIB's effect was. Reasons that LAIB may not last the full inter‐dosing interval include individual variation in opioid response, the normal distribution of plasma levels [31], or the absence of plasma‐level fluctuations seen with shorter‐acting opioids [32, 33], which may provide reassurance of ongoing effect. Medication factors, for example dose titration challenges, or delays in reaching steady‐state, which can take up to four doses [34], may also have an effect. Participants' perspectives on effectiveness also shifted over time in the study, suggesting utility from future work to explore such changes during longer‐term treatment. While this finding is consistent with existing general population literature [30], it is important to highlight in the CJS where unplanned release and limited flexibility, due to factors such as clinic availability, lockdowns and staff shortages, may make timely or ad‐hoc administration difficult. This highlights the need for flexible treatment models, particularly for clients who report cravings or withdrawal symptoms. These implications may be especially important in the post‐release period, as the duration of OAT‐associated reduction in risk of opioid use and overdose may otherwise be overestimated.

Participants in our study reported reduced substance use, including non‐opioids which, while not explained pharmacologically, has been similarly reported in other buprenorphine research [35, 36], though inconsistently [30]. This is particularly relevant in CJS settings, as substance use may be shaped by institutional conditions and can lead to significant debts, increasing exposure to violence or coercion [37]. Some participant comments suggested misconceptions about whether buprenorphine formulations ‘block’ other opioids, highlighting the importance of clear education to support informed use.

Perceptions of LAIB were impacted by aspects not strictly relating to the medication or treatment. For example, psychological factors, likely shaped by sociocultural backgrounds [9], influenced perceptions of LAIB's effectiveness. However, some experiences described as psychological may also have had pharmacological explanations, including reaching steady‐state. Peer influence and misconceptions, such as rubbing the injection site for greater medication effect, were present after only brief periods of treatment, which is particularly striking given LAIB's novelty when this study was undertaken. This highlights the importance of addressing preconceptions before and during treatment, with peer workers likely well placed to support this process.

The importance of participants' agency was evident across multiple themes but featured most prominently in relation to confidence in the medication effect. There is value in future studies exploring whether outcomes differ when LAIB is initiated based on patient preference versus limited availability of OAT options. This is particularly relevant in settings, such as the CJS, where LAIB may be the system's preferred OAT due to concerns such as diversion and limited resourcing.

4.2. Frequency of Dosing

LAIBs' reduced dosing frequency was discussed frequently by participants though perspectives again varied. Such variation may indicate that certain subpopulations may benefit from daily‐dosing, such as those who find its reliability psychologically reassuring. Alternatively, preference for daily‐dosing may arise from the subtle plasma concentration fluctuations experienced with SL‐BUP dosing which are referred to in Cheng et al. [15] as a daily‐dosing ‘boost’. This again highlights the importance of flexibility and tailoring treatment as core messages from this work.

The finding of increased time and ‘normalcy’ as key considerations in LAIB's acceptability is particularly relevant in the CJS given that these populations often experience unpredictable and demanding life circumstances, where added convenience can be especially beneficial. Indeed, Stopka et al. [16] reported that LAIB could represent the ‘next step’ towards stability because it was less habit‐forming than daily‐dosing and future work exploring this would be of particular interest. However, the routine of daily‐dosing may provide a sense of stability for some participants‐ a finding that is supported by other CJS and general population studies [16, 38], and has previously been found to shift over time and varied circumstances [39].

4.3. Social and Relational Considerations

The finding that participants experienced reduced stigma relative to SL‐BUP is significant given the well‐documented effects of stigma on health and wellbeing [40, 41]. This was echoed in other general population [42] and CJS papers [15, 16], and is highly significant in the prison setting given the compounded stigma often experienced by this population [43]. Conversely, internalised stigma around prescribed OAT persisted, such as a participant describing LAIB as ‘still a drug’. While interpretation of this was limited by the depth of responses, this view echoes abstinence‐only ideologies which carry greater risk than approaches which included OAT [39, 44] and remains important to address with patients.

LAIB's impact on diversion was complex, with both benefits and challenges explored. Diversion is especially relevant in CJS settings, where institutional concerns may result in restrictions to OAT availability [45], and where patients' choice in treatment may be affected by diversion pressures [46]. Stopka et al. [16] reported that some participants felt ‘forced’ onto LAIB when other OAT options were removed, particularly as a punitive response to diversion. This did not arise in our study, potentially because LAIB was only available through the UNLOC‐T study at the time. As LAIB becomes more widely and potentially preferentially prescribed in CJS settings, any implications of such decisions for patients’ autonomy and treatment outcomes may become increasingly apparent [6, 7, 8].

While most participants viewed changes in social interaction associated with LAIB positively, context remained important, with some noting that these perspectives may shift post‐release. Concerns about privacy from prison officers also suggest that stigma and treatment acceptability may be experienced differently in prison than in the community. Indeed, general population studies have shown nuances, with changes to perspectives on social interactions over the course of treatment [14].

4.4. Health and Wellbeing

Our study highlighted health and wellbeing as central to participants' experience and decision‐making. As with other themes, participants' preferences and experiences were quite unique, highlighting the need for flexibility in treatment and tailoring OAT selection to the individual. Mental health particularly was emphasised, with some participants finding LAIB helpful while others found it detrimental. Notably, a paper looking at patient reported outcomes from UNLOC‐T showed improvements in psychological distress and quality of life with LAIB [20]. Nevertheless, this is not universal and it is therefore prudent to screen for mental health concerns in the period following commencement with LAIB, particularly given the high level of baseline mental health issues for people in the CJS [47, 48]. Longer‐term and post‐release studies examining impacts on mental health and personal development would be beneficial.

The injectable route of administration was a barrier for some participants in our study, as with existing CJS and general population studies [15, 16, 39, 49]. This was due to the injection site side‐effects, which are experienced by ~5%–10% of people [50], as well as the injection and injecting equipment inciting cravings, which may be more prevalent in this trial where LAIB was offered to participants not on OAT prior to enrolment than in a population already stable on OAT. Some participants in Stopka et al. [16] reported longstanding needle phobia and coming to OAT from a background of oral opioid use, which emphasises the need for person‐centred care.

Participants described how their experiences of side effects, either from LAIB or OAT formulations, affected acceptability. Changes to energy levels and possible withdrawal symptoms (e.g., body aches, hot flushes) were perceived as side effects, however they could also reflect ongoing illicit SL‐BUP use, a supra‐ or sub‐therapeutic treatment dose or other physiological effects of buprenorphine. It is also important to note that the LAIB arm of the trial included participants who were not on OAT at baseline, rather they predominantly used non‐prescribed SL‐BUP non‐medically. The reported effects could differ if comparing LAIB in a population stable on OAT, and for whom more accurate estimated dose equivalencies may be possible. Participants also expressed concern about possible long‐term effects of this relatively new treatment, reflective of findings in Stopka et al. [16] in the CJS and general population [51]. Future research could explore how side effects and concerns evolve over time and throughout the treatment course, particularly given that when an individual achieves steady‐state with LAIB depends on the dose and dosing interval [52], may take up to four administrations to achieve after each dose or formulation change [31], and that LAIB is now more widely used [6, 7, 8].

4.5. Finances

Our findings align with existing research suggesting that LAIB may improve access to employment both in the CJS [15] and general community [9, 14, 53]. It is particularly important in the CJS, however, given that employment post‐release is protective against reoffending [54]. Our participants' reports of reduced expenditure on substance use are notable, particularly in the CJS, where unpaid drug‐related debts can lead to violence [37].

4.6. Strengths and Limitations

A key limitation of this study is the use of short open‐ended questions within surveys. The results are therefore unlikely to capture the depth and diversity of experiences that semi‐structured interviews can achieve. Responses were researcher transcribed at the time of the interview and may have been open to misinterpretation given the brevity in some responses, potentially limiting validity. The brevity of responses also meant that interpretative analysis would have been difficult, and we therefore undertook a primarily descriptive coding strategy focused on participants' stated experiences rather than latent meanings. This emphasis on practical relevance was well suited to the data and allowed us to develop insights that could directly inform service improvement and patient care.

There were also contextual limitations in our study, including that the participants were incarcerated and may not have felt comfortable responding freely due to potential consequences. Additionally, our data was collected as a part of a clinical trial, when LAIB was a novel treatment, to people not on OAT but primarily using non‐prescribed SL‐BUP (see Appendix A) who would not otherwise have had access to prescribed OAT. Such a background could impact participants' perspectives on LAIB, including difficulty in initially estimating dose equivalencies and potentially leading to underdosing. Since the UNLOC‐T trial was undertaken, LAIB has been rolled out in many CJS [5, 55], and indeed some services have begun to preferentially, or even exclusively, use LAIB over other forms of OAT which could impact treatment experiences. This trial was also conducted in a single system rather than across multiple networks and consequently may not reflect the perspectives of people in other contexts.

Finally, while a high number of participants responded to week 4 questions, responses reduced later in the trial, and key perspectives may be missing as a result. It is also important to consider that the week 4 quotes reflect the perspectives of individuals who are only just achieving steady‐state and may not be indicative of the longer‐term experience of LAIB, particularly in terms of medication effectiveness and frequency of dosing.

Despite these limitations, our study has several strengths. Firstly, our study is an important addition to the existing literature as it was conducted with currently incarcerated people, where existing studies have solely focused on recently released populations [15, 16]. Secondly, the trial took place early in LAIB adoption and so may more accurately reflect experiences of LAIB‐naïve populations. Such results are no longer accessible as knowledge and preconceived expectations of LAIB have grown with use. Additionally, our use of a survey‐style allowed for a sample size of 67, with strong female and Aboriginal representation which is often underrepresented in CJS literature. This size is particularly notable given that both existing CJS‐based studies had smaller sample sizes of 16 [15] and 38 [16]. The latter trial also included a variety of OAT modalities, with only 11% (n = 4) being on LAIB [16]. Moreover, our design enabled longer follow‐up than the existing CJS literature on LAIB, which focuses primarily on the treatment initiation phase [15, 16]. Importantly, open‐ended surveys have not previously been used in this setting and therefore provided an opportunity to triangulate findings from the previously published semi‐structured interviews [15, 16]. Indeed, our findings showed consistency across many of the themes found in both existing CJS [15, 16] and general population papers [9, 51, 56].

5. Conclusions

Our findings align closely with previous LAIB research in both CJS and general population settings, while also making an important contribution to the evidence base. Structural, ethical, and implementation barriers in CJS settings mean that findings from community samples cannot be presumed to translate directly into correctional settings. Our study provides insights into how LAIB is experienced in the CJS, while also strengthening the relevance of the existing LAIB literature for a population historically excluded from clinical research.

5.1. Individualised, Person‐Centred and Evolving Treatment

A key finding from this work is that LAIB offers many benefits and is an important OAT option. However, LAIB was not universally preferred or beneficial, with varied perspectives across themes, over time, and potentially across settings. This supports an individualised, person‐centred approach, ideally offering LAIB as one of several options through shared‐decision making. This is consistent with Australian OAT guidelines which recommend taking client preferences into account when selecting treatment [57, 58]. Our emphasis on capturing observable and recurrent experiences and concerns allowed us to identify themes that may help guide discussions with patients as to which OAT option is most appropriate and highlights the need to revisit treatment decisions over time. This includes aspects such as formulation, dose, supplemental dosing and dosing interval. General population studies have conceptualised this as part of the therapeutic alliance between provider and patient and posited the importance of considering the disconnection in this alliance when exploring why people cease treatment [13].

5.2. Implications of the Study

These findings have important implications for clients, prescribers, and policy‐makers. In particular, while it is understandable that funding and operational constraints may lead correctional services to consider LAIB as the default or sole option, our findings suggest that ensuring client autonomy and treatment choice should remain a central consideration in OAT provision. Service models should therefore endeavour to support flexibility and responsiveness, rather than prioritising service efficiency alone.

5.3. Future Research Directions

Future studies tracking patients' longitudinal experiences with LAIB during and beyond incarceration could allow for a more in‐depth understanding of treatment optimisation, particularly in terms of evolving acceptability and the nature of stigma. Triangulation with quantitative treatment outcomes such as retention, alongside in‐depth interviews across pre‐ and post‐release settings, with interpretive analysis particularly around areas such as autonomy and confidence in treatment, would offer deeper insights into treatment. Perspectives from justice and health services, family members, and broader system stakeholders would also be valuable given that prison systems and structures have been identified as barriers affecting OAT delivery [59]. Continued research in the CJS remains important as these settings have unique challenges compared to community environments, an understanding of which is critical for informing policy and practice.

Author Contributions

Each author certifies that their contribution to this work meets the standards of the International Committee of Medical Journal Editors. A.W. led data analysis and manuscript drafting. C.F. and M.D. contributed to coding, development of the descriptive coding strategy within a thematic framework, and substantive manuscript drafting and revision. A.D., B.W., N.L., P.S.H. and J.R. contributed to study design, protocol development, review of thematic outputs, and refinement of the framing and presentation of findings. All authors approved the final version.

Funding

This work was supported by the National Drug and Alcohol Research Centre; Australian Government Research Training Program.

Conflicts of Interest

Hunter New England and Sydney Local Health Districts, who employ A.D. and P.S.H., have received funding from Camurus AB and Indivior, who manufacture long‐acting injectable buprenorphine formulations. A.D. has also been on an advisory board (honorary) for Camurus AB. South Eastern Sydney Local Health District, which employs N.L., has received research funding from Camurus AB for unrelated research. A.W., C.F., J.R., E.E., B.W. and M.D. declare no conflicts of interest.

Appendix A.

UNLOCT Study Design and Context

Context	At the commencement of this trial in 2018, there was no capacity for the main healthcare provider for the NSW CJS to provide OAT to all individuals with OUD, and LAIB was not widely available either in the CJS or in the general community. In Australian CJS, the most accessible recreational opioid was generally illicit or diverted SL‐BUP. At this time, methadone was often preferred in CJS health systems due to its lower diversion potential than SL‐BUP. Therefore, in this study, when participants compared LAIB to SL‐BUP, it is likely that many people's experiences of SL‐BUP were extramedical rather than through a formal OAT program, and often with varied routes of administration such as inhaled or injected. It is also important to note that at this time there was a significant proportion of the CJS population who met OUD criteria but due to staffing requirements for prescribing and administering methadone were not able to be commenced on OAT. This is the population that was recruited into the UNLOC‐T study.
Procedure	Briefly, in 2018–2019 adults in seven public correctional centres across six metropolitan and rural areas of NSW who were not receiving OAT nor deemed as a priority to access existing OAT (e.g., HIV positive, pregnant women, significant medical illness) but had evidence of an moderate–severe OUD and who had a minimum of 6 months left on their sentence, were offered LAIB as a part of the UNLOC‐T study. LAIB was administered weekly for 4 weeks, then monthly injections for a further 12 weeks. Participants were offered ongoing LAIB treatment beyond the 16‐week trial under the ‘Extended Safety Monitoring phase’ of the study in Week 20 to 48 which included ongoing monthly injections and safety monitoring. At the commencement of the trial, LAIB was originally administered in the formulation CAM‐2038, but was changed to Buvidal, which is the same medication but in a different stock, following its successful registration by the Therapeutic Good Administration in. The study included a comparator arm of people who were stable on oral methadone, however the comparator arm was not included in this qualitative analysis. CAM2038 weekly for once‐weekly administration was available at doses 16, 24 and 32 mg buprenorphine and CAM2038 monthly for once‐monthly administration was available at doses 64, 96, 128 or 160 mg buprenorphine base. Participants in the LAIB arm were initiated to treatment with a 4 mg test‐dose of sublingual buprenorphine‐naloxone film (Day 0) and observed for 1 h to confirm opioid tolerability. Treatment with study drug was initiated with a single dose of CAM2038 weekly 16 mg injection on day 1. Patients received a total of four doses of CAM2038 weekly (day 1, week 1, week 2 and week 3) before transferring to three doses of CAM2038 monthly (week 4, week 8 and week 12). If required, patients could receive an additional 8 mg CAM2038 weekly injection, up to a maximum dose 32 mg for the weekly injections and a maximum of 160 mg for the monthly injections, with at least 1 day between each supplemental 8 mg injection. Doses of CAM2038 weekly could be titrated up or down between 16 mg and 32 mg while doses of CAM2038 monthly could be titrated up or down between 64 mg monthly and 160 mg.
Relevant results	Prevalence and frequency of use Baseline: Non prescribed opioids 65/67 (97.01%) 4 weeks: 41/67 (61.19%) 8 weeks: 8/67 (12.31%)

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.