Monkeypox in Montréal: Epidemiology, Phylogenomics, and Public Health Response to a Large North American Outbreak.

BACKGROUND: Monkeypox, a viral zoonotic disease, is causing a global outbreak outside of endemic areas. OBJECTIVE: To characterize the outbreak of monkeypox in Montréal, the first large outbreak in North America. DESIGN: Epidemiologic and laboratory surveillance data and a phylogenomic analysis were used to describe and place the outbreak in a global context. SETTING: Montréal, Canada. PATIENTS: Probable or confirmed cases of monkeypox. MEASUREMENTS: Epidemiologic, clinical, and demographic data were aggregated. Whole-genome sequencing and phylogenetic analysis were performed for a set of outbreak sequences. The public health response and its evolution are described. RESULTS: Up to 18 October 2022, a total of 402 cases of monkeypox were reported mostly among men who have sex with men (MSM), most of which were suspected to be acquired through sexual contact. All monkeypox genomes nested within the B.1 lineage. Montréal Public Health worked closely with the affected communities to control the outbreak, becoming the first jurisdiction to offer 1 dose of the Modified Vaccinia Ankara-Bavarian Nordic vaccine as preexposure prophylaxis (PrEP) to those at risk in early June 2022. Two peaks of cases were seen in early June and July (43 and 44 cases per week, respectively) followed by a decline toward near resolution of the outbreak in October. Reasons for the biphasic peak are not fully elucidated but may represent the tempo of vaccination and/or several factors related to transmission dynamics and case ascertainment. LIMITATIONS: Clinical data are self-reported. Limited divergence among sequences limited genomic epidemiologic conclusions. CONCLUSION: A large outbreak of monkeypox occurred in Montréal, primarily among MSM. Successful control of the outbreak rested on early and sustained engagement with the affected communities and rapid offer of PrEP vaccination to at-risk persons. PRIMARY FUNDING SOURCE: None.

Ledipasvir-Sofosbuvir Plus Ribavirin in Treatment-Naive Patients With Hepatitis C Virus Genotype 3 Infection: An Open-Label Study.

BACKGROUND: Patients chronically infected with genotype 3 hepatitis C virus (HCV) have faster disease progression and are less responsive to current direct-acting antiviral regimens than patients infected with other genotypes. We conducted an open-label trial to evaluate the safety, tolerability, and efficacy of ledipasvir and sofosbuvir plus ribavirin in patients with genotype 3 HCV infection. METHODS: We enrolled treatment-naive patients with and without compensated cirrhosis at 15 sites in Canada. All patients were treated with ledipasvir-sofosbuvir (90 mg and 400 mg) plus weight-based ribavirin for 12 weeks. The primary endpoint was sustained virologic response 12 weeks after treatment (SVR12). Secondary endpoints included evaluation of baseline and treatment-emergent drug resistance. RESULTS: Of the 111 patients enrolled, 105 (95%) had subtype 3a HCV and 39 (35%) had compensated cirrhosis. SVR12 was achieved by 99 of 111 patients (89%; 95% confidence interval, 82%-94%). Of the 39 patients with cirrhosis, 31 (79%) achieved SVR12, compared with 68 of 72 (94%) patients without cirrhosis. No treatment-emergent resistance mutations occurred in those who failed treatment. One patient discontinued treatment due to liver cancer and died 22 days after treatment discontinuation. The most common adverse events were fatigue (51%), headache (36%), and nausea (23%). CONCLUSIONS: In this multicenter trial involving treatment-naive patients with genotype 3 HCV, 12 weeks of ledipasvir-sofosbuvir provided a high level of SVR in those without cirrhosis. CLINICAL TRIALS REGISTRATION: NCT02413593.

Adherence to Post-Exposure Prophylaxis (PEP) and Incidence of HIV Seroconversion in a Major North American Cohort.

BACKGROUND: There is limited evidence on the efficacy of post-exposure prophylaxis (PEP) for sexual exposures. We sought to determine the factors associated with adherence to treatment and describe the incidence of PEP failures in a Montreal clinic. METHODS: We prospectively assessed all patients consulting for PEP following sexual exposures from October 2000 to July 2014. Patients were followed at 4 and 16 weeks after starting PEP. Treatment adherence was determined by self-report at week 4. Multivariable logistic regression was used to estimate the factors predicting adherence to treatment. RESULTS: 3547 PEP consults were included. Patients were mainly male (92%), MSM (83%) and sought PEP for anal intercourse (72%). Seventy-eight percent (n = 2772) of patients received a prescription for PEP, consisting of Tenofovir/Emtracitabine (TVD) + Lopinavir/Ritonavir (LPV) in 74% of cases, followed by Zidovudine/Lamivudine (CBV) + LPV (10%) and TVD + Raltegravir (RAL) (8%). Seventy percent of patients were adherent to treatment. Compared to TVD+LPV, patients taking CBV+LPV were less likely to adhere to treatment (OR 0.58, 95% CI 0.44-0.75), while no difference was observed for patients taking TVD+RAL (OR 1.15, 95% CI 0.83-1.59). First-time PEP consults, older and male patients were also more adherent to treatment. Ten treated patients seroconverted (0.37%) during the study period, yet only 1 case can be attributed to PEP failure (failure rate = 0.04%). CONCLUSION: PEP regimen was associated with treatment adherence. Patients were more likely to be adherent to TVD-based regimens. Ten patients seroconverted after taking PEP; however, only 1 case was a PEP failure as the remaining patients continued to engage in high-risk behavior during follow-up. One month PEP is an effective preventive measure to avoid HIV infection.

Tolerability is more important than simplicity for treatment durability.

INTRODUCTION: Many studies have shown the superiority of single tablet regimens (STRs) of antiretrovirals for the treatment of HIV in terms of efficacy, adherence and rate of hospitalisation as they offer a low pill burden and once daily dosing. Our objective was to compare the duration of first-line STRs to multi-tablet regimens. METHODS: From our clinical database, we selected patients initiating any of the major first-line regimens between 2007 and 2013. Two STRs, Atripla (ATP) and Complera (CPLR), were compared to three non-STRs: two NRTIs and raltegravir (RAL), atazanavir/ritonavir (ATV/r) or darunavir/ritonavir (DRV/r). The primary outcome was time to discontinuation of the first-line regimen. The association between regimen type and duration was estimated using Cox proportional hazards models adjusted for age, gender, baseline CD4, baseline viral load, risk factor, site and year of treatment initiation. RESULTS: A total of 743 patients (281 on STRs and 462 on non-STRs) were included. 693 (93%) were male and median age was 43 years. Median length of follow-up was 3.2 years. 56% of patients were MSM, 6% IDU and 6% from endemic countries. Patients on an STR were less likely to be IDU (p<0.024) and have a baseline HIV-RNA ≥100,000 copies/mL (p<0.011). Overall, 321 (43%) patients discontinued their regimen during the study period. The rate of discontinuation one year after starting ARV depends on the regimen: 29% for patients on 2NRTIs+DRV/r, 26% on ATP, 25% on 2NRTIs+ATV/r, 17% on 2NRTIs+RAL and 10% on CPLR (p<0.001). In the adjusted model, durability for STR and non-STR was equivalent (aHR=0.83, p=0.108). Compared to patients on ATP, patients on CPLR were less likely to discontinue (HR=0.58, p=0.070). No difference between ATP and the other regimens was observed: HR for 2NRTIs+RAL=0.92 (p=0.66), 2NRTIs+ DRV/r=1.16 (p=0.36), 2NRTIs+ATV/r=1.11 (p=0.46). CONCLUSIONS: Our findings suggest that STRs do not necessarily result in a more durable treatment. Even with a higher pill burden and/or twice daily dosing, patients initiating therapy with RAL or boosted-PI based regimens were not more likely to discontinue the first-line regimen compared to patients on an STR. Among the STR subgroups, the regimen with better known tolerability conferred more durable treatment. Limitations included our inability to adjust for the patient's adherence to a given regimen.