Clinical and histological features of histiocytoid Sweet syndrome associated with VEXAS syndrome.

BACKGROUND: "Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic" (VEXAS) syndrome is caused by acquired somatic mutations in the ubiquitin-activating enzyme 1 (UBA1) gene. Sweet-syndrome-like skin disorders (and especially histiocytoid Sweet syndrome (HSS)) may be associated with VEXAS syndrome. OBJECTIVE: To characterize the clinical and histopathological features of HSS in patients with VEXAS syndrome. METHODS: The skin biopsies with a histological diagnosis of HSS had been collected at Rennes University Medical Center (Rennes, France) between October 2011 and January 2022. Sanger sequencing and digital PCR were used to screen skin, blood, and bone marrow samples for UBA1 variants, and thus classify patients as having VEXAS syndrome or not. We evaluated the clinical, histological, and molecular (UBA1) characteristics of patients with or without VEXAS syndrome. RESULTS: We compared 15 skin biopsies from seven patients found to have VEXAS syndrome and 19 skin biopsies from 15 patients without VEXAS syndrome. Persistent inflammatory syndrome, macrocytosis, anemia, and hematological malignancies were more prevalent in patients with VEXAS syndrome (86%, 86%, 100%, and 86%, respectively) than in patients without (36%, 40%, 53%, and 53%, respectively). These features sometimes appeared after the first skin manifestations, and a UBA1 mutation was found in the skin of five patients with VEXAS syndrome. Dermal infiltration by myeloperoxidase-positive, CD163-positive, reniform histiocytoid cells and a periadnexal distribution were more frequently observed in VEXAS syndrome biopsies (100% and 20% respectively, vs. 58% and 0% in non-VEXAS syndrome biopsies, respectively). CONCLUSION: Our findings might help the pathologist to consider a diagnosis of VEXAS syndrome and to initiate early genetic testing.

Sustained Remission Without Corticosteroids Among Patients With Pemphigus Who Had Rituximab as First-Line Therapy: Follow-Up of the Ritux 3 Trial.

Importance: The Ritux 3 trial demonstrated the short-term efficacy and safety of first-line treatment with rituximab compared with a standard corticosteroid regimen in pemphigus. No data on the long-term follow-up of patients who received rituximab as first line are available. Objective: To assess the long-term efficacy and safety of the Ritux 3 treatment regimen. Design, Setting, and Participants: This 7-year follow-up study of the Ritux 3 trial included patients with pemphigus from 25 dermatology departments in France from January 1, 2010, to December 31, 2015. Exposure: Patients were initially randomized in the rituximab plus prednisone group or prednisone-alone group. Main outcomes and measures: The primary outcome was the 5- and 7-year disease-free survival (DFS) without corticosteroids, assessed by Kaplan-Meier curves. Secondary outcomes were occurrence of relapse, occurrence of severe adverse events (SAEs), and evolution of antidesmoglein (Dsg) antibody enzyme-linked immunosorbent assay values to predict long-term relapse. Results: Of the 90 patients in the Ritux 3 trial, 83 were evaluated at the end of follow-up study visit (44 in the rituximab plus prednisone group; 39 in the prednisone-alone group) with a median (IQR) follow-up of 87.3 (79.1-97.5) months. Forty-three patients (93%) from the rituximab plus prednisone and 17 patients (39%) from the prednisone-alone group had achieved complete remission without corticosteroids at any time during the follow-up. Patients from the rituximab group had much longer 5- and 7-year DFS without corticosteroids than patients from the prednisone-alone group (76.7% and 72.1% vs 35.3% and 35.3%, respectively; P < .001), and had about half the relapses (42.2% vs 83.7%; P < .001). Patients who received rituximab as second-line treatment had shorter DFS than patients treated as first line (P = .007). Fewer SAEs were reported in the rituximab plus prednisone group compared with the prednisone-alone group, 31 vs 58 respectively, corresponding to 0.67 and 1.32 SAEs per patient, respectively (P = .003). The combination of anti-Dsg1 values of 20 or more IU/mL and/or anti-Dsg3 values of 48 or more IU/mL yielded 0.83 positive predictive value and 0.94 negative predictive value to predict long-term relapse. Conclusions and Relevance: In this secondary analysis of the Ritux 3 trail, first-line treatment of patients with pemphigus with the Ritux 3 regimen was associated with long-term sustained complete remission without corticosteroid therapy without any additional maintenance infusion of rituximab.

Clinical features, therapeutic choice and response by phototype in psoriasis: analysis of the French PsoBioTeq cohort.

BACKGROUND: Little is known about phototype and the response to systemic treatment in psoriasis. OBJECTIVES: To assess the characteristics of psoriasis, the therapeutic choice and its efficacy according to phototype. METHODS: We included patients from the PsoBioTeq cohort initiating a first biologic. Patients were classified according to their phototype. The evaluation included disease characteristics, choice of the initial biologic and therapeutic response at 12 months based on 90% improvement from baseline in Psoriasis Area and Severity Index (PASI 90) and Dermatology Life Quality Index (DLQI) 0/1. RESULTS: Of the 1400 patients included, 423 (30.2%), 904 (64.6%) and 73 (5.2%) were in the phototype I-II, III-IV and V-VI groups, respectively. The V-VI group had a higher initial DLQI, and more frequently initiated ustekinumab. Patients in the V-VI group maintained the initial biologic prescribed as did the other phototype groups, even though the proportion of patients reaching PASI 90 and DLQI 0/1 at 12 months was lower in this group than the other groups. CONCLUSIONS: Patient phototype seems associated with quality of life and choice of the initial biologic in psoriasis. The phototype V-VI group less frequently switched treatments than did the other groups when the response was not efficient.

Major adverse cardiovascular events in patients with atopic dermatitis treated with oral Janus kinase inhibitors: a systematic review and meta-analysis.

BACKGROUND: On the basis of safety data for patients with inflammatory rheumatism or inflammatory bowel disease, treatment with Janus kinase (JAK) inhibitors (JAKi) has been linked to the occurrence of major adverse cardiovascular events (MACE). However, these inflammatory diseases are proatherogenic; in contrast, patients with atopic dermatitis (AD) do not usually have a high cardiovascular (CV) comorbidity burden. OBJECTIVES: To perform a systematic review and meta-analysis of MACE in patients with AD treated with JAKi. METHODS: We systematically searched PubMed, Embase, Cochrane Library and Google Scholar from their inception to 2 September 2022. Cohort studies, randomized controlled trials and pooled safety analyses providing CV safety data on patients taking JAKi for AD were selected. We included patients aged ≥ 12 years. We built a 'controlled-period' cohort (n = 9309; 6000 exposed to JAKi and 3309 exposed to comparators) and an 'all-JAKi' cohort (n = 9118 patients exposed to a JAKi in any of the included studies). The primary outcome was a composite of acute coronary syndrome (ACS), ischaemic stroke and CV death. The broader secondary MACE outcome encompassed ACS, stroke (whether ischaemic or haemorrhagic), transient ischaemic attack and CV death. The frequency of primary and secondary MACE was assessed in both cohorts. A fixed-effects meta-analysis using the Peto method was used to calculate the odds ratio (OR) for MACE in the 'controlled-period' cohort. Evaluation of the risk of bias was done using the Cochrane risk-of-bias tool (version 2). Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. RESULTS: Eight per cent of the records identified initially met the selection criteria, corresponding to 23 records included in the 'all-JAKi' cohort. Patients had been exposed to baricitinib, upadacitinib, abrocitinib, ivarmacitinib, placebo or dupilumab. Four primary events (three with JAKi and one with placebo) and five secondary events (four with JAKi and one with placebo) occurred among 9309 patients in the 'controlled-period' cohort (MACE frequency 0.04% and 0.05%, respectively). Eight primary events and 13 secondary events occurred among 9118 patients in the 'all-JAKi' cohort (MACE frequency 0.08% and 0.14%, respectively). The OR for primary MACE in patients with AD treated with JAKi vs. placebo or dupilumab was 1.35 (95% confidence interval 0.15-12.21; I2 = 12%, very low certainty of evidence). CONCLUSIONS: Our review highlights rare cases of MACE among JAKi users for AD. JAKi may have little-to-no effect on the occurrence of MACE in patients with AD vs. comparators, but the evidence is uncertain. Real-life long-term population-level safety studies are needed.

Efficacy of Methotrexate Alone vs Methotrexate Plus Low-Dose Prednisone in Patients With Alopecia Areata Totalis or Universalis: A 2-Step Double-Blind Randomized Clinical Trial.

Importance: Poor therapeutic results have been reported in patients with alopecia areata totalis (AT) or universalis (AU), the most severe and disabling types of alopecia areata (AA). Methotrexate, an inexpensive treatment, might be effective in AU and AT. Objective: To evaluate the efficacy and tolerance of methotrexate alone or combined with low-dose prednisone in patients with chronic and recalcitrant AT and AU. Design, Setting, and Participants: This academic, multicenter, double-blind, randomized clinical trial was conducted at 8 dermatology departments at university hospitals between March 2014 and December 2016 and included adult patients with AT or AU evolving for more than 6 months despite previous topical and systemic treatments. Data analysis was performed from October 2018 to June 2019. Interventions: Patients were randomized to receive methotrexate (25 mg/wk) or placebo for 6 months. Patients with greater than 25% hair regrowth (HR) at month 6 continued their treatment until month 12. Patients with less than 25% HR were rerandomized: methotrexate plus prednisone (20 mg/d for 3 months and 15 mg/d for 3 months) or methotrexate plus placebo of prednisone. Main Outcome and Measures: The primary end point assessed on photos by 4 international experts was complete or almost complete HR (Severity of Alopecia Tool [SALT] score <10) at month 12, while receiving methotrexate alone from the start of the study. Main secondary end points were the rate of major (greater than 50%) HR, quality of life, and treatment tolerance. Results: A total of 89 patients (50 female, 39 male; mean [SD] age, 38.6 [14.3] years) with AT (n = 1) or AU (n = 88) were randomized: methotrexate (n = 45) or placebo (n = 44). At month 12, complete or almost complete HR (SALT score <10) was observed in 1 patient and no patient who received methotrexate alone or placebo, respectively, in 7 of 35 (20.0%; 95% CI, 8.4%-37.0%) patients who received methotrexate (for 6 or 12 months) plus prednisone, including 5 of 16 (31.2%; 95% CI, 11.0%-58.7%) who received methotrexate for 12 months and prednisone for 6 months. A greater improvement in quality of life was observed in patients who achieved a complete response compared with nonresponder patients. Two patients in the methotrexate group discontinued the study because of fatigue and nausea, which were observed in 7 (6.9%) and 14 (13.7%) patients receiving methotrexate, respectively. No severe treatment adverse effect was observed. Conclusions and Relevance: In this randomized clinical trial, while methotrexate alone mainly allowed partial HR in patients with chronic AT or AU, its combination with low-dose prednisone allowed complete HR in up to 31% of patients. These results seem to be of the same order of magnitude as those recently reported with JAK inhibitors, with a much lower cost. Trial Registration: ClinicalTrials.gov Identifier: NCT02037191.

Anti-BP180 IgG antibody ELISA values correlate with adverse pregnancy outcomes in pemphigoid gestationis.

BACKGROUND: Adverse pregnancy outcomes (APO) occur in 35% of patients with pemphigoid gestationis (PG). No biological predictor of APO has been established yet. OBJECTIVES: To assess a potential relationship between the occurrence of APO and the serum value of anti-BP180 antibodies at the time of PG diagnosis. METHODS: Multicentre retrospective study conducted from January 2009 to December 2019 in 35 secondary and tertiary care centres. INCLUSION CRITERIA: (i) diagnosis of PG according to clinical, histological and immunological criteria, (ii) ELISA measurement of anti-BP180 IgG antibodies determined at the time of PG diagnosis with the same commercial kit and (iii) obstetrical data available. RESULTS: Of the 95 patients with PG included, 42 had one or more APO, which mainly corresponded to preterm birth (n = 26), intrauterine growth restriction (IUGR) (n = 18) and small weight for gestational age at birth (n = 16). From a ROC curve, we identified a threshold of 150 IU ELISA value as the most discriminating to differentiate between patients with or without IUGR, with 78% sensitivity, 55% specificity, 30% positive and 91% negative predictive value. The threshold >150 IU was confirmed using a cross-validation based on bootstrap resampling, which showed that the median threshold was 159 IU. Upon adjusting for oral corticosteroid intake and main clinical predictors of APO, an ELISA value of >150 IU was associated with the occurrence of IUGR (OR = 5.11; 95% CI: 1.48-22.30; p = 0.016) but not with any other APO. The combination of blisters and ELISA values higher than 150 IU led to a 2.4-fold higher risk of all-cause APO (OR: 10.90; 95% CI: 2.33-82.3) relative to patients with blisters but lower values of anti-BP180 antibodies (OR of 4.54; 95% CI 0.92-34.2). CONCLUSION: These findings suggest that anti-BP180 antibody ELISA value in combination with clinical markers is helpful in managing the risk of APO, in particular IUGR, in patients with PG.

The concomitant use of proton pump inhibitors and BRAF/MEK inhibitors in metastatic melanoma.

BACKGROUND: Proton-pump inhibitors (PPIs) are commonly used by patients with cancer, although they could reduce the absorption of oral anticancer targeted therapies. The US Food and Drug Administration states that the effect of PPIs on the efficacy of dabrafenib use by patients with metastatic melanoma is unknown. As a precautionary measure, the European Society for Medical Oncology recommends avoiding PPIs for patients receiving dabrafenib. OBJECTIVES: To determine the effect of the concomitant use of PPIs and BRAF/MEK inhibitors in patients with metastatic melanoma. METHODS: Patients with advanced melanoma receiving BRAF/MEK inhibitors as first-line treatments between 2015 and 2017 in France were selected using the French National Health Insurance database. We compared time-to-treatment discontinuation (TTD) and overall survival (OS) according to concomitant PPI exposure. We balanced the baseline characteristics of patients exposed and nonexposed to PPIs using an overlap weighting method based on a propensity score. RESULTS: The metastatic melanoma cohort comprised 1028 patients receiving BRAF/MEK inhibitors, including 361 (35.1%) patients using PPIs. PPI users had more comorbidities and a more severe metastatic disease. After having equally distributed metastatic sites and comorbidities across patients exposed and nonexposed to PPIs, concomitant PPI use was not associated with shorter TTD [weighted hazard ratio (wHR) 1.03, 95% confidence interval (CI) 0.86-1.24] or OS (wHR 1.11, 95% CI 0.88-1.39). Consistent results were observed when restricting the population to patients receiving dabrafenib, or when narrowing exposure to PPIs with stronger inhibition of cytochromes. CONCLUSIONS: In a population-based cohort of patients with advanced melanoma, the concomitant use of PPIs and BRAF/MEK inhibitors was not associated with worse outcome.

Bone involvement in primary cutaneous diffuse large B-cell lymphoma, leg-type.

Primary cutaneous diffuse large B-cell lymphoma, leg-type (PCDLBCL-LT) is an aggressive cutaneous lymphoma. Bone involvement is rare and poorly described. We present five cases of PCDLBCL-LT with bone localization. In four cases, the bone involvement was diagnosed during the initial staging with positron emission tomography (PET) or computed tomography (CT) scan, and in the fifth case after tibial fracture during treatment with rituximab (RTX) and polychemotherapy (PCT). PCDLBCL-LT can be asymptomatic and involve bone sites distant from cutaneous lesions. None had other extracutaneous involvement. In our series, all patients received RTX-PCT as first-line chemotherapy and all had early relapses or progression. Second-line treatments had poor efficacy. Our series shows that bone involvement seems to be associated with poor prognosis in PCDLBCL-LT. Bone localization is not diagnosed with initial thoracic-abdominal-pelvic CT when asymptomatic and affecting the limbs only. If there is a suspicion of PCDLBCL-LT, patients should undergo systematic investigation with alternative imaging techniques, including PET, both at baseline and if there is any concern during follow-up.

Treatment of dissecting cellulitis of the scalp with tumour necrosis factor inhibitors: a retrospective multicentre study.

Although retinoids are considered as the most effective treatment, management of dissecting cellulitis of the scalp (DCS) is often challenging. A multicentre retrospective study was conducted to evaluate the efficacy of anti-tumour necrosis factor (TNF) agents in treating DCS after failure of other conventional treatments. Twenty-six patients were included. After a mean treatment duration of 19 months (SD 21), the median Physician's Global Assessment score decreased from 3 to 1. The median number of inflammatory nodules and abscesses decreased from 7 to 0.5 and from 1 to 0, respectively. The median Dermatology Life Quality Index and numerical rating scale score for pain severity decreased from 10 to 8 and 6 to 1, respectively. The median treatment satisfaction was 7 out of 10 on the Patient Satisfaction Index. This study confirms the efficacy of anti-TNF agents in treating patients with DCS that is resistant to conventional therapies.

Cost-Effectiveness Analysis of Sequential Treatment Strategies for Advanced Melanoma in Real Life in France.

Nine drugs have been marketed for 10 years for the treatment of advanced melanoma (AM). With half of patients reaching a second line, the optimal sequence of treatments remains unclear. To inform policy-makers about their efficiency, we performed a cost-effectiveness analysis of sequential strategies in clinical practice in France, for BRAF-mutated and wild-type patients. A multistate model was developed to describe treatment sequences, associated costs, and health outcomes over 10 years. Sequences, clinical outcomes, utility scores, and economic data were extracted from the prospective Melbase cohort, collecting individual data in 1518 patients since 2013, from their AM diagnosis until their death. To adjust the differences in patients' characteristics among sequences, weighting by inverse probability was used. In the BRAF-mutated population, the MONO-targeted therapies (TT)-anti-PD1 sequence was the less expensive, whereas the anti-PD1-BI-TT sequence had an incremental cost-effectiveness ratio (ICER) of 180,441 EUR/QALY. Regarding the BRAF wild-type population, the three sequences constituted the cost-effective frontier, with ICERs ranging from 116 to 806,000 EUR/QALY. For BRAF-mutated patients, the sequence anti-PD1-BI-TT appeared to be the most efficient one in BRAF-mutated AM patients until 2018. Regarding the BRAF wild-type population until 2018, the sequence starting with IPI+NIVO appeared inefficient compared to anti-PD1, considering the extra cost for the QALY gained.

Safety and efficacy of nivolumab, an anti-PD1 immunotherapy, in patients with advanced basal cell carcinoma, after failure or intolerance to sonic Hedgehog inhibitors: UNICANCER AcSé NIVOLUMAB trial.

BACKGROUND: Basal cell carcinoma (BCC) is the most common human malignancy. In most cases, BCC has slow progression and can be definitively cured by surgery or radiotherapy. However, in rare cases, it can become locally advanced or, even more rarely, metastatic. The alternative recommended treatments are Sonic Hedgehog pathway inhibitors; however, the response is often short-lived. METHODS: This was a phase 2 basket study (NCT03012581) evaluating the efficacy and safety of nivolumab in a cohort of 32 advanced BCC patients, enrolled after failure of Sonic Hedgehog inhibitors, including 29 laBCC (91%) and 3 mBCC (9%). RESULTS: Compared to previously published studies, our population consisted of severe patients with a poor prognosis because they had already received multiple lines of treatment: all patients received previous Sonic Hedgehog inhibitors, 53% of patients already had chemotherapy and 75% radiotherapy. At 12 weeks, we reported 3.1% of complete responses, 18.8% of partial responses, and 43.8% of stable diseases. The best response rate to nivolumab reached 12.5% of complete responses (four patients), 18.8% of partial responses (three patients), and 43.8% of stable diseases (14 patients). Adverse events (AE) were mostly grade 2 or 3, slightly different to the adverse events observed in the treatment of metastatic melanoma (higher rate of diabetes, no thyroid dysfunction). CONCLUSION: Nivolumab is a relevant therapeutic option for patients with advanced relapsing/refractory BCC.

Oral Janus kinase inhibitors and venous thromboembolic events in atopic dermatitis: protocols for a case-time control study and a nested case-control study based on the French national health insurance (SNDS) cohort.

INTRODUCTION: Atopic dermatitis (AD) is a highly prevalent, chronic, inflammatory skin disease. Several orally administered Janus kinase inhibitors (JAKis, including baricitinib, upadacitinib and abrocitinib) have received a marketing authorisation for AD.Clinical trials in rheumatoid arthritis (RA) have flagged up a potential risk of JAKi-induced venous thromboembolic events (VTEs). Accordingly, the summary of product characteristics for a JAKi must mention VTEs as potential adverse drug reactions. In contrast to RA, AD per se is not associated with an elevated risk of VTEs. Assessing this potential risk among patients with AD would shed further light on the putative underlying relationship between JAKis and VTEs.Our research question is to investigate whether JAKi administration increases the risk of VTEs in adults with AD. Our primary objective is to assess the risk of VTEs in adults with AD exposed to JAKis compared to AD adults not exposed to JAKis, and our secondary objective is to evaluate whether JAKi initiation acts as a trigger of VTEs in adults with AD within 3 months. METHODS AND ANALYSIS: Hence, we have designed (1) a nested case-control study and (2) a case-time control study in a cohort of adults with AD with data from the French national health insurance system (2017-2025).Here, we describe the study protocol, our methodological choices and certain novel aspects, including the combined value of the two assumptions and the use of an exhaustive national health insurance database with potentially greater statistical power for studying rare events in the population of patients with AD at a low risk of VTEs (thus limiting the influence of confounding factors). ETHICS AND DISSEMINATION: The protocol has been approved by an independent ethics committee and registered with the French National Data Protection Commission. The study's findings will be published in peer-reviewed scientific journals and presented at international conferences.

Impact of Distribution of a Tip Sheet to Increase Early Detection and Prevention Behavior among First-Degree Relatives of Melanoma Patients: A Randomized Cluster Trial.

BACKGROUND: First-degree relatives (FDRs, defined as parents, children, and siblings) of melanoma patients are at a two-to-fivefold increased risk of developing melanoma themselves. FDRs are advised to perform self-skin examination (SSE) and annual medical total cutaneous examination (TCE) performed either by a dermatologist or a general practitioner, and to change their sun-related behavior. This advice is given orally to melanoma patients who are asked to relay the information to their FDRs. OBJECTIVE: Our aim was to determine the impact of providing a tip sheet to melanoma patients intended to their first-degree relatives (FDRs) on early detection and sun-related behaviors in this group at increased risk of melanoma. METHODS: A superiority, cluster-randomized trial was conducted at nine hospital centers. In the intervention group, dermatologists were asked to deliver to melanoma patients (index cases) the tip sheet and oral advice intended to their FDRs. The control group were asked to deliver the usual oral advice alone. The primary outcome was early detection of melanoma in FDRs with a medical TCE performed within one year after the first visit of the index case. Secondary outcomes were SSE and sun-related behaviors in FDRs. RESULTS: A total of 48 index cases and 114 FDRS in the control group, 60 index cases and 166 FDRS in the intervention group were recruited. In the intervention group, 36.1% of FDRs performed a medical TCE as compared to 39.5% of FDRs in the control group (OR 0.9 [95% CI 0.5 to 1.5], p = 0.63). We did not find a between-group difference in SSE and sun-related behaviors. CONCLUSION: A tip sheet added to the usual oral advice did not increase medical TCE among FDRs of melanoma patients. Overall, the rate of TCE among FDRs was low. Research on other strategies is needed to increase melanoma detection in this population.

Impact of Childhood Onset Psoriasis on Addictive Behaviours, Socioeconomic and Educational Data in Adulthood.

Paediatric psoriasis has been associated with school absenteeism, limitation of physical activities, psychiatric disorders and, in the longer term, with sexual dysfunction and addictions. This raises the hypothesis that childhood onset psoriasis may affect patients' educational development, and further social and professional outcomes. This study evaluated the relationship between childhood onset psoriasis and patients' educational and socioeconomic characteristics, and the development of addictions in adulthood. This cross-sectional ancillary study captured patients' characteristics at baseline in the French PSOBIOTEQ registry. Data in adulthood included: educational (baccalaureate) and socioeconomic (working activity) groups, smoking status (self-reporting of being a current smoker vs past smoker or non-smoker), alcohol consumption (defined as at least 1 glass of alcoholic beverage per day), and living conditions (alone/family/social institutions; child at home). A total of 1,960 patients were included, of whom 26.2% had childhood onset psoriasis. In multivariate analyses, childhood onset psoriasis was associated with smoker status (p = 0.02). No association was observed with educational level, working activity, living conditions, or alcohol consumption. This study provides reassuring data overall with regard to the impact of childhood onset psoriasis on major social outcomes. Evidence for some association with addictive behaviours paves the way for larger prospective studies assessing in depth the social and educational impact of this disease.

The Association Between Antibiotic Use and Outcome Among Metastatic Melanoma Patients Receiving Immunotherapy.

BACKGROUND: Several observational studies have reported a decreased response to immune checkpoint inhibitors (ICI) following antibiotic use. ICI activity has been hypothesized to be impaired by antibiotic-induced gut dysbiosis. METHODS: Patients with advanced melanoma receiving an anti-PD-1 antibody as a first-line therapy between 2015 and 2017 in France were selected using the French Health Insurance database. We compared overall survival and time-to-treatment discontinuation according to antibiotic exposure in the 3 months prior to the initiation of anti-PD-1 antibody. To disentangle a causal effect of antibiotics from a confounding bias, we balanced characteristics of patients exposed and nonexposed to antibiotics using an overlap weighting method based on a propensity score. We also evaluated a control cohort of patients with advanced melanoma receiving first-line targeted therapy, as there is no rationale for decreased efficacy of targeted therapy following antibiotic treatment. RESULTS: The anti-PD-1 antibody cohort comprised 2605 individuals. Antibiotic exposure in the 3 months prior to anti-PD-1 antibody initiation was not associated with shorter overall survival (weighted hazard ratio = 1.01, 95% confidence interval = 0.88 to 1.17) or time-to-treatment discontinuation (weighted hazard ratio = 1.00, 95% confidence interval = 0.89 to 1.11). Consistent results were observed when the time frame of antibiotics was narrowed to 1 month prior to anti-PD-1 initiation or when exposure was restricted to antibiotics leading to more profound gut dysbiosis. Similar results were observed in the targeted therapy cohort. CONCLUSIONS: In a large cohort of advanced melanoma patients, we showed that antibiotic use preceding anti-PD-1 antibody was not associated with worse outcome. Physicians should not delay immunotherapy for patients who have recently received antibiotics.