Risk of hospitalization and death due to infection in people with psoriasis: a population-based cohort study using the Clinical Practice Research Datalink.

BACKGROUND: Psoriasis is associated with risk factors for serious infections, but the independent relationship between psoriasis and serious infection is as yet unclear. OBJECTIVES: To determine whether people with psoriasis have a higher risk of hospitalization due to any infection, respiratory infections, soft-tissue and skin infections, or a higher risk of death due to infection. METHODS: We conducted a cohort study of people (≥ 18 years) with psoriasis using the UK Clinical Practice Research Datalink (CPRD GOLD) linked to Hospital Episode Statistics (HES) and Office for National Statistics (ONS) mortality records between 1 April 2003 and 31 December 2016, and matched with up to six comparators on age, sex and general practice. Hospitalization was ascertained from HES records; death was ascertained from ONS mortality records. Stratified Cox proportional hazard models were estimated, with stepwise adjustment in different models for potential confounders or mediators between psoriasis and serious infection. RESULTS: There were 69 315 people with psoriasis and 338 620 comparators who were followed up for a median (interquartile range) of 4·9 (5·9) and 5·1 (6·3) years, respectively. People with psoriasis had a higher incidence rate of serious infection [20·5 per 1000 person-years, 95% confidence interval (CI) 20·0-21·0, n = 7631] compared with those without psoriasis (16·1 per 1000 person-years, 95% CI 15·9-16·3, n = 30 761). The fully adjusted hazard ratio for the association between psoriasis and serious infection was 1·36 (95% CI 1·31-1·40), with similar results across the other outcomes. CONCLUSIONS: Psoriasis is associated with a small increase in the risk of serious infection. Further research is needed to understand how psoriasis predisposes to a higher risk of infection.

Global Guidelines in Dermatology Mapping Project (GUIDEMAP): a scoping review of dermatology clinical practice guidelines.

BACKGROUND: Clinical practice guidelines (CPGs) play a critical role in standardizing and improving treatment outcomes based on the available evidence. It is unclear how many CPGs are available globally to assist clinicians in the management of patients with skin disease. OBJECTIVES: To search for and identify CPGs for dermatological conditions with the highest burden globally. METHODS: We adapted a list of 12 dermatological conditions with the highest burden from the Global Burden of Disease (GBD) study 2019. A systematic literature search was done to identify CPGs published between October 2014 to October 2019. The scoping review was conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework. RESULTS: A total of 226 CPGs were included. Melanoma had the greatest representation in the CPGs, followed by dermatitis and psoriasis. Skin cancers had a relatively high CPG representation but with lower GBD disease burden ranking. There was an uneven distribution by geographical region, with resource-poor settings being under-represented. The skin disease categories of the CPGs correlated weakly with the GBD disability-adjusted life-years metrics. Eighty-nine CPGs did not have funding disclosures and 34 CPGs were behind a paywall. CONCLUSIONS: The global production of dermatology CPGs showed wide variation in geographical representation, article accessibility and reporting of funding. The number of skin disease CPGs were not commensurate with its disease burden. Future work will critically appraise the methodology and quality of dermatology CPGs and lead to the production of an accessible online resource summarizing these findings.

Risk-mitigating behaviours in people with inflammatory skin and joint disease during the COVID-19 pandemic differ by treatment type: a cross-sectional patient survey.

BACKGROUND: Registry data suggest that people with immune-mediated inflammatory diseases (IMIDs) receiving targeted systemic therapies have fewer adverse coronavirus disease 2019 (COVID-19) outcomes compared with patients receiving no systemic treatments. OBJECTIVES: We used international patient survey data to explore the hypothesis that greater risk-mitigating behaviour in those receiving targeted therapies may account, at least in part, for this observation. METHODS: Online surveys were completed by individuals with psoriasis (globally) or rheumatic and musculoskeletal diseases (RMDs) (UK only) between 4 May and 7 September 2020. We used multiple logistic regression to assess the association between treatment type and risk-mitigating behaviour, adjusting for clinical and demographic characteristics. We characterized international variation in a mixed-effects model. RESULTS: Of 3720 participants (2869 psoriasis, 851 RMDs) from 74 countries, 2262 (60·8%) reported the most stringent risk-mitigating behaviour (classified here under the umbrella term 'shielding'). A greater proportion of those receiving targeted therapies (biologics and Janus Kinase inhibitors) reported shielding compared with those receiving no systemic therapy [adjusted odds ratio (OR) 1·63, 95% confidence interval (CI) 1·35-1·97]. The association between targeted therapy and shielding was preserved when standard systemic therapy was used as the reference group (OR 1·39, 95% CI 1·23-1·56). Shielding was associated with established risk factors for severe COVID-19 [male sex (OR 1·14, 95% CI 1·05-1·24), obesity (OR 1·37, 95% CI 1·23-1·54), comorbidity burden (OR 1·43, 95% CI 1·15-1·78)], a primary indication of RMDs (OR 1·37, 95% CI 1·27-1·48) and a positive anxiety or depression screen (OR 1·57, 95% CI 1·36-1·80). Modest differences in the proportion shielding were observed across nations. CONCLUSIONS: Greater risk-mitigating behaviour among people with IMIDs receiving targeted therapies may contribute to the reported lower risk of adverse COVID-19 outcomes. The behaviour variation across treatment groups, IMIDs and nations reinforces the need for clear evidence-based patient communication on risk-mitigation strategies and may help inform updated public health guidelines as the pandemic continues.

Drug survival of adalimumab, ustekinumab and secukinumab in patients with psoriasis: a prospective cohort study from the British Association of Dermatologists Biologics and Immunomodulators Register (BADBIR).

BACKGROUND: Real-world biologic drug survival is an important proxy measure for effectiveness. Predictors of drug survival may help patients with psoriasis choose between biologic therapies. OBJECTIVES: (i) To assess the relative drug survival of adalimumab, ustekinumab and secukinumab in patients with psoriasis. (ii) To investigate predictors of biologic drug survival. METHODS: A prospective cohort study was performed in the British Association of Dermatologists Biologics and Immunomodulators Register (BADBIR) between November 2007 and August 2019. We performed survival analysis and fitted a flexible parametric survival model for biologic discontinuation due to ineffectiveness. RESULTS: In total 9652 patients were included: 5543 starting on adalimumab (57·4%), 991 on secukinumab (10·3%) and 3118 on ustekinumab (32·3%). The overall drug survivals of adalimumab, secukinumab and ustekinumab in year 1 were 0·78 [95% confidence interval (CI) 0·77-0·79], 0·88 (95% CI 0·86-0·91) and 0·88 (95% CI 0·87-0·89), respectively. The adjusted hazard ratios (adjHRs) for discontinuation of adalimumab and secukinumab compared with ustekinumab were 2·11 (95% CI 1·76-2·54) and 0·67 (95% CI 0·40-1·11), respectively. The presence of psoriatic arthritis predicted for survival in the adalimumab and secukinumab cohorts (adjHR 0·67, 95% CI 0·51-0·88 and 0·70, 95% CI 0·40-1·24, respectively), but for discontinuation in the ustekinumab cohort (adjHR 1·42, 95% CI 1·12-1·81). Previous exposure to biologic therapies predicted for discontinuation in the ustekinumab and secukinumab cohorts (adjHR 1·54, 95% CI 1·26-1·89 and 1·49, 95% CI 0·91-2·45, respectively) and for survival in the adalimumab cohort (adjHR 0·71, 95% CI 0·55-0·92). CONCLUSIONS: Secukinumab and ustekinumab have similar sustained drug survival, while adalimumab has a lower drug survival in patients with psoriasis. Psoriatic arthritis and previous biologic experience were predictors with differential effects between the biologic therapies. What is already known about this topic? There is conflicting evidence over the real-world drug survival of secukinumab in patients with psoriasis. Data from registries to date suggest that secukinumab has a lower drug survival than that reported from clinical trials. What does this study add? This study found that secukinumab and ustekinumab had similar sustained drug survival in the real world, while the drug survival of adalimumab was lower, suggesting that the real-world drug survival of secukinumab is higher than previously reported. We found that psoriatic arthritis and previous biologic experience had differential effects on drug discontinuation in the three biologic cohorts. These predictors may help patients and clinicians choose the most appropriate biologic therapy.

Comparing the efficacy and tolerability of biologic therapies in psoriasis: an updated network meta-analysis.

BACKGROUND: The rapid expansion of psoriasis biologics has led to an urgent need to understand their relative efficacy and tolerability to inform treatment decisions better and, specifically, to inform guideline development. OBJECTIVES: To update a 2017 meta-analysis on the comparative efficacy and tolerability of biologic treatments for psoriasis. METHODS: We searched the MEDLINE, PubMed, Embase and Cochrane databases for randomized controlled trials (RCTs), published up to 7 September 2018, of 11 licensed, NICE-approved biologics targeting tumour necrosis factor (adalimumab, etanercept, infliximab, certolizumab pegol), interleukin (IL)-12/IL-23p40 (ustekinumab), IL-17A (secukinumab, ixekizumab), IL-17RA (brodalumab) and IL-23p19 (guselkumab, tildrakizumab, risankizumab). A frequentist network meta-analysis ascertained direct or indirect evidence comparing biologics with one another, methotrexate or placebo. This was combined with hierarchical cluster analyses to consider efficacy (≥ 90% improvement in Psoriasis Area and Severity Index (PASI 90) or Physician's Global Assessment 0 or 1; PASI 75; Dermatology Life Quality Index improvement) and tolerability (drug withdrawal due to adverse events) outcomes at 10-16 weeks, followed by assessments of study quality, heterogeneity and inconsistency. RESULTS: We identified 62 RCTs presenting data on direct comparisons (31 899 participants). All biologics were efficacious compared with placebo or methotrexate at 10-16 weeks. Hierarchical cluster analyses revealed that adalimumab, brodalumab, certolizumab pegol, guselkumab, risankizumab, secukinumab, tildrakizumab and ustekinumab were comparable with respect to high short-term efficacy and tolerability. Infliximab and ixekizumab clustered together, with high short-term efficacy but relatively lower tolerability than the other agents, although the number of drug withdrawal events across the network was low, so these findings should be treated with caution. CONCLUSIONS: Using our methodology we found that most biologics cluster together with respect to short-term efficacy and tolerability, and we did not identify any single agent as 'best'. These data need to be interpreted in the context of longer-term efficacy, effectiveness data, safety, posology and drug acquisition costs when making treatment decisions.

Risankizumab vs. ustekinumab for plaque psoriasis: a critical appraisal.

AIM: Gordon et al. investigated the efficacy and safety of risankizumab [an anti-interleukin (IL)-23p19 biologic] compared with ustekinumab (anti-IL-12/23p40) and placebo in patients with moderate-to-severe chronic plaque psoriasis. This was a parallel-group controlled study up to 16 weeks with a planned switch of the placebo group to risankizumab at 16 weeks. SETTING AND DESIGN: This study consisted of two replicate phase III, double-blinded randomized controlled trials (UltIMMa-1 and UltIMMa-2) conducted across 139 centres in Australia, Austria, Belgium, Canada, Czech Republic, France, Germany, Japan, Mexico, Poland, Portugal, South Korea, Spain and the U.S.A. STUDY EXPOSURE: Patients with a minimum 6-month history of chronic plaque psoriasis were randomly assigned to receive either 150 mg risankizumab, 45 mg or 90 mg ustekinumab or placebo. Prior to this, each group was also stratified by weight (either more than or less than 100 kg) and previous exposure to tumour necrosis factor inhibitors. Those assigned to receive placebo were transitioned onto risankizumab at week 16. The study drugs were given at weeks 0, 4, 16, 28 and 40. OUTCOMES: The severity of psoriasis was measured using the Psoriasis Area and Severity Index (PASI) and a static Physician's Global Assessment (sPGA). The authors additionally recorded the number of adverse events in each treatment arm, and a measure of quality of life. PRIMARY OUTCOME MEASURES: The coprimary outcomes were the proportions of patients achieving ≥ 90% reduction in their baseline PASI (PASI 90) and an sPGA score of 0 or 1 (clear or almost clear) at week 16. RESULTS: In total 506 patients were included in UltIMMa-1 and 491 patients in UltIMMa-2. In UltIMMa-1, PASI 90 by week 16 was achieved by 75·3% of patients receiving risankizumab, compared with 42·0% receiving ustekinumab and 4·9% receiving placebo (P < 0·001 vs. placebo and ustekinumab). sPGA of 0 or 1 by week 16 was achieved by 87·6% of patients receiving risankizumab, compared with 63·0% receiving ustekinumab and 7·8% receiving placebo (P < 0·001 vs. placebo and ustekinumab). The results for UltIMMa-2 are similar. The frequencies of adverse events in the risankizumab, ustekinumab and placebo groups were similar in both studies. CONCLUSIONS: Gordon et al. conclude that risankizumab has a higher efficacy than placebo and ustekinumab in the treatment of moderate-to-severe chronic plaque psoriasis, and that the adverse-event profiles were similar across all treatment groups.

Development and validation of a multivariable risk prediction model for serious infection in patients with psoriasis receiving systemic therapy.

BACKGROUND: Patients with psoriasis are often concerned about the risk of serious infection associated with systemic psoriasis treatments. OBJECTIVES: To develop and externally validate a prediction model for serious infection in patients with psoriasis within 1 year of starting systemic therapies. METHODS: The risk prediction model was developed using the British Association of Dermatologists Biologic Interventions Register (BADBIR), and the German Psoriasis Registry PsoBest was used as the validation dataset. Model discrimination and calibration were assessed internally and externally using the C-statistic, the calibration slope and the calibration in the large. RESULTS: Overall 175 (1·7%) out of 10 033 participants from BADBIR and 41 (1·7%) out of 2423 participants from PsoBest developed a serious infection within 1 year of therapy initiation. Selected predictors in a multiple logistic regression model included nine baseline covariates, and starting infliximab was the strongest predictor. Evaluation of model performance showed a bootstrap optimism-corrected C-statistic of 0·64 [95% confidence interval (CI) 0·60-0·69], calibration in the large of 0·02 (95% CI -0·14 to 0·17) and a calibration slope of 0·88 (95% CI 0·70-1·07), while external validation performance was poor, with C-statistic 0·52 (95% CI 0·42-0·62), calibration in the large 0·06 (95% CI -0·25 to 0·37) and calibration slope 0·36 (95% CI -0·24 to 0·97). CONCLUSIONS: We present the first results of the development of a multivariable prediction model. This model may help patients and dermatologists in the U.K. and the Republic of Ireland to identify modifiable risk factors and inform therapy choice in a shared decision-making process.

Infliximab is associated with an increased risk of serious infection in patients with psoriasis in the U.K. and Republic of Ireland: results from the British Association of Dermatologists Biologic Interventions Register (BADBIR).

BACKGROUND: Patients with psoriasis and clinicians are concerned that infliximab may be associated with a risk of serious infections. OBJECTIVES: To compare the risk of serious infections associated with infliximab in patients with chronic plaque psoriasis against a cohort on nonbiologic systemic therapies. METHODS: A prospective cohort study was performed using data from the British Association of Dermatologists Biologic Interventions Register (BADBIR). Infliximab was compared with nonbiologic systemic therapies, inclusive of any exposure to methotrexate, ciclosporin, acitretin, fumaric acid esters, psoralen-ultraviolet A or hydroxycarbamide. Serious infections were those associated with hospitalization, the use of intravenous antimicrobial therapy and/or those that led to death. Propensity score inverse probability treatment weights were used to adjust for potential confounding from a priori identified covariates. Cox proportional hazards models were calculated to obtain hazard ratios (HRs). RESULTS: In total, 3843 participants were included for analysis up to October 2016. The incidence rates were significantly higher in the infliximab cohort (47·8 per 1000 person-years) [95% confidence interval (CI) 35·7-64·0], compared with 14·2 per 1000 person-years (95% CI 11·5-17·4) in the nonbiologic systemic cohort. Infliximab was associated with an overall increase in the risk of serious infection compared with nonbiologics [adjusted HR (adjHR) 1·95, 95% CI 1·01-3·75] and methotrexate only (adjHR 2·96, 95% CI 1·58-5·57) and a higher risk of serious infection in the first 6 months of therapy (adjHR 3·49, 95% CI 1·14-10·70). CONCLUSIONS: Infliximab is associated with an increased risk of serious infections compared with nonbiologic systemic therapies in patients with psoriasis in the U.K. and the Republic of Ireland.

A standardization approach to compare treatment safety and effectiveness outcomes between clinical trials and real-world populations in psoriasis.

BACKGROUND: Patients recruited in randomized controlled trials (RCTs) for biologic therapies in psoriasis are not fully representative of the real-world psoriasis population. OBJECTIVES: Firstly, to investigate whether patient characteristics are associated with being included in a psoriasis RCT. Secondly, to estimate the differences in the incidence of severe adverse events (SAEs) and the response rate between RCT and real-world populations of patients on biologic therapies for psoriasis using a standardization method. METHODS: Data from the British Association of Dermatologists Biologics and Immunomodulators Register (BADBIR) were appended to individual participant-level data from two RCTs assessing ustekinumab in patients with psoriasis. Baseline variables were assessed for association of being in an RCT using a multivariable logistic regression model. Propensity score weights were derived to reweigh the registry population so that variables had the distribution of the trial population. We measured the C-statistic of the model with trial status as the dependent variable, and the risk differences in the incidence rate of SAEs in the first year and Psoriasis Area and Severity Index (PASI) after 6 months in the BADBIR cohort before and after weighting. RESULTS: In total 6790 registry and 2021 RCT participants were included. The multivariable logistic regression model had a C-statistic of 0.82 [95% confidence interval (CI) 0.81-0.83]. The risk differences for the incidence rate of SAEs and the proportion of patients with PASI < 1.5 were 9.27 (95% CI -3.91-22.5) per 1000 person-years and 0.95 (95% CI -1.98-4.15), respectively. CONCLUSIONS: Our results suggest that RCTs of biologic therapies in patients with psoriasis are not fully representative of the real-world population, but this lack of external validity does not account for the efficacy-effectiveness gap. What's already known about this topic? Patients with psoriasis who would not be eligible for randomized controlled trials (RCTs) investigating biologic therapies have a greater risk of serious adverse events and lower treatment effectiveness than patients who would have been eligible. What does this study add? Baseline patient characteristics were shown to be predictive of whether a patient would have been eligible for enrolment in an RCT for psoriasis biologic therapy. We did not find any efficacy-effectiveness gap between the sample representative of the real-world population of patients with psoriasis and the sample representative of the RCT population. Factors outside of baseline patient characteristics, such as observer effect and higher adherence in RCTs, may be more influential in any efficacy-effectiveness gap between trial and real-world populations of patients with psoriasis.

Persistence and effectiveness of nonbiologic systemic therapies for moderate-to-severe psoriasis in adults: a systematic review.

BACKGROUND: The persistence and effectiveness of systemic therapies for moderate-to-severe psoriasis in current clinical practice are poorly characterized. OBJECTIVES: To systematically review observational studies investigating the persistence and effectiveness of acitretin, ciclosporin, fumaric acid esters (FAE) and methotrexate, involving at least 100 adult patients with moderate-to-severe psoriasis, exposed to therapy for ≥ 3 months. METHODS: MEDLINE, Embase, the Cochrane Library and PubMed were searched from 1 January 2007 to 1 November 2017 for observational studies reporting on persistence (therapy duration or the proportion of patients discontinuing therapy during follow-up) or effectiveness [improvements in Psoriasis Area and Severity Index (PASI) or Physician's Global Assessment (PGA)]. This review was registered with PROSPERO, number CRD42018099771. RESULTS: Of 411 identified studies, eight involving 4624 patients with psoriasis were included. Variations in the definitions and analyses of persistence and effectiveness outcomes prevented a meta-analysis from being conducted. One prospective multicentre study reported drug survival probabilities of 23% (ciclosporin), 42% (acitretin) and 50% (methotrexate) at 1 year. Effectiveness outcomes were not reported for either acitretin or ciclosporin. The persistence and effectiveness of FAE and methotrexate were better characterized, but mean discontinuation times ranged from 28 to 50 months for FAE and 7·7 to 22·3 months for methotrexate. At 12 months of follow-up, three studies reported that 76% (FAE), 53% (methotrexate) and 59% (methotrexate) of patients achieved ≥ 75% reduction in PASI, and one reported that 76% of FAE-exposed patients achieved a markedly improved or clear PGA. CONCLUSIONS: The comparative persistence and effectiveness of acitretin, ciclosporin, FAE and methotrexate in real-world clinical practice in the past decade cannot be well described due to the inconsistency of the methods used.

Impact of biologic therapies on risk of major adverse cardiovascular events in patients with psoriasis: systematic review and meta-analysis of randomized controlled trials.

Concerns have been raised regarding an increased risk of major adverse cardiovascular events (MACEs) (myocardial infarction, cerebrovascular accident or cardiovascular death) in patients treated with anti-interleukin (IL)-12/23 agents for moderate-to-severe psoriasis. We aimed to examine the risk of MACEs in adult patients with plaque psoriasis that are exposed to biologic therapies via a meta-analysis of randomized controlled trials (RCTs). Data were obtained from systematic searches in the Cochrane Library, MEDLINE and Embase, U.S. Food and Drug Administration, European Medicines Agency, individual pharmaceutical companies online search platforms and five trials registers (up to 31 March 2016). We selected RCTs reporting adverse events in adults with plaque psoriasis receiving at least one licensed dose of biologic therapy, conventional systematic therapy or placebo. We calculated Peto odds ratios (ORs) with 95% confidence intervals (CIs) and calculated I2 statistics to assess heterogeneity. Overall, 38 RCTs involving 18 024 patients were included. No MACEs were observed in 29 studies, while nine RCTs reported 10 patients experiencing MACEs. There was no statistically significant difference in risk of MACEs associated with the use of biologic therapies overall (OR 1·45, 95% CI 0·34-6·24); tumour necrosis factor-α inhibitors (adalimumab, etanercept and infliximab) (OR 0·67, 95% CI 0·10-4·63); anti-IL-17A agents (secukinumab and ixekizumab) (OR 1·00, 95% CI 0·09-11·09) or ustekinumab (OR 4·48, 95% CI 0·24-84·77). No heterogeneity was observed in these comparisons. In conclusion, the limited existing evidence suggests that licensed biologic therapies are not associated with MACEs during the short randomized controlled periods in clinical trials.

Early- and late-onset psoriasis: a cross-sectional clinical and immunocytochemical investigation.

BACKGROUND: There is accumulating evidence that early-onset psoriasis (EOP; presenting at or before 40 years of age) and late-onset psoriasis (LOP; presenting after 40 years of age) are different diseases. OBJECTIVES: We aimed to identify potential clinical and immunocytochemical differences between EOP and LOP. METHODS: We assessed immunocytochemistry in involved (PP) skin and uninvolved skin (n = 31) and demographics, psoriasis phenotype and psychological parameters (n = 340) in a cross-sectional study. RESULTS: Immunocytochemistry revealed (17 EOP, 14 LOP) a greater lymphocytic infiltrate in PP skin of EOP compared with LOP (P = 0·03), with a higher epidermal CD4+ : CD8+ ratio in LOP (1·3) compared with EOP (0·5) (P = 0·002). In 340 patients with psoriasis (278 EOP, 62 LOP), we found an association with a positive first or second degree family history of psoriasis [62·0% vs. 35·6%, adjusted odds ratio (OR) 8·32, 95% confidence interval (CI) 1·90-36·52] and a higher likelihood of having parents with EOP (adjusted OR 10·34, 95% CI 1·32-81·83) in the EOP group. Patients with EOP were more likely to have received biological therapy (13·3% EOP vs. 3·5% LOP, P = 0·042), while patients with LOP had a higher likelihood of having type 2 diabetes (adjusted OR 3·43, 95% CI 1·004-11·691) and autoimmune thyroiditis (adjusted OR 5·05, 95% CI 1·62-15·7). Patients with LOP also had greater anxiety than patients with EOP (mean Hospital Anxiety and Depression Scale-A score LOP 8 ± 5, EOP 5 ± 5; P = 0·006). CONCLUSIONS: Our findings provide further evidence for the difference between EOP and LOP.

Paradoxical exacerbation of chronic plaque psoriasis by sorafenib.

Vascular endothelial growth factor (VEGF) antagonists have been investigated as a potential treatment for psoriasis, but there have been reports of VEGF antagonists triggering and/or exacerbating pre-existing psoriasis. We present the case of a 61-year old-man with exacerbation of pre-existing psoriasis after treatment with sorafenib, a small molecule inhibitor of the tyrosine kinase domain of the VEGF receptor, and we review the literature for other published cases of sorafenib-induced or sorafenib-exacerbated psoriasis. Clinicians, including both dermatologists and oncologists, should be aware of this potential side-effect of sorafenib in addition to the other cutaneous side effects reported for this drug.