Risk of natalizumab-associated progressive multifocal leukoencephalopathy.

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is associated with natalizumab treatment. We quantified the risk of PML in patients with multiple sclerosis, according to the presence or absence of three risk factors: positive status with respect to anti-JC virus antibodies, prior use of immunosuppressants, and increasing duration of natalizumab treatment. METHODS: We used data from postmarketing sources, clinical studies, and an independent Swedish registry to estimate the incidence of PML among natalizumab-treated patients with multiple sclerosis, according to positive or negative status with respect to anti-JC virus antibodies, prior or no prior use of immunosuppressants, and duration of treatment (1 to 24 months vs. 25 to 48 months). Blood samples were available for anti-JC virus antibody testing from 5896 patients with multiple sclerosis and from 54 patients with multiple sclerosis who were treated with natalizumab and in whom PML later developed. RESULTS: As of February 29, 2012, there were 212 confirmed cases of PML among 99,571 patients treated with natalizumab (2.1 cases per 1000 patients). All 54 patients with PML for whom samples were available before the diagnosis were positive for anti-JC virus antibodies. When the risk of PML was stratified according to three risk factors, the risk of PML was lowest among the patients who were negative for anti-JC virus antibodies, with the incidence estimated to be 0.09 cases or less per 1000 patients (95% confidence interval [CI], 0 to 0.48). Patients who were positive for anti-JC virus antibodies, had taken immunosuppressants before the initiation of natalizumab therapy, and had received 25 to 48 months of natalizumab treatment had the highest estimated risk (incidence, 11.1 cases per 1000 patients [95% CI, 8.3 to 14.5]). CONCLUSIONS: Positive status with respect to anti-JC virus antibodies, prior use of immunosuppressants, and increased duration of natalizumab treatment, alone or in combination, were associated with distinct levels of PML risk in natalizumab-treated patients with multiple sclerosis. (Funded by Biogen Idec and Elan Pharmaceuticals.).

Low-contrast acuity measures visual improvement in phase 3 trial of natalizumab in relapsing MS.

OBJECTIVE: Low-contrast letter acuity has demonstrated treatment effects for sustained visual loss in trials of natalizumab for relapsing multiple sclerosis (MS). To test new therapies that may involve neuroprotection and repair, it will be essential for outcome measures to detect improvement as well as loss of visual function. We determined the effects of natalizumab on the frequency and cumulative probability of visual improvement using low-contrast letter acuity a prespecified tertiary outcome measure in AFFIRM. METHODS: AFFIRM was a randomized, double-blind, placebo-controlled, phase 3 trial that evaluated efficacy and safety of natalizumab (n=627) vs. placebo (n=315) in relapsing-remitting MS. Binocular acuities were measured at low-contrast (1.25%, 2.5%) and high-contrast visual acuity (VA). Improvement was defined as 12-week sustained increases from baseline. Clinically meaningful change for primary analyses was pre-defined as 7-letter improvement for low-contrast acuity and 5-letter improvement for VA based upon previous studies. RESULTS: Compared to placebo, cumulative probabilities of sustained visual improvement were greater in the natalizumab group by 57% for 2.5% contrast (21.7% vs. 14.0%; HR=1.57; 95% CI: 1.11-2.22; P=0.012) and 39% for 1.25% contrast (32.5% vs. 25.0%; HR=1.39; 95% CI: 1.07-1.82; P=0.014). The 5- and 10-letter low-contrast assessments did not show treatment differences. High-contrast VA was insensitive to changes over time and treatment effects. CONCLUSION: Low-contrast letter acuity detected treatment effects on sustained visual improvement in patients with relapsing MS. The ability to detect visual improvement and loss makes low-contrast acuity an important measure for future trials assessing the impact of therapy on this outcome and the potential of a therapy for neuroprotection and repair.

Anti-John Cunnigham virus antibody prevalence in multiple sclerosis patients: baseline results of STRATIFY-1.

OBJECTIVE: A study was undertaken to define the prevalence of anti-JC virus (JCV) antibodies in multiple sclerosis (MS) patients and to evaluate the analytical false-negative rate of a 2-step anti-JC virus antibody assay. METHODS: STRATIFY-1 is an ongoing, longitudinal, observational study of relapsing MS patients in the United States who are being treated or considering treatment with natalizumab. Baseline serum and plasma samples were collected for anti-JC virus antibody detection using an analytically validated, 2-step, virus-like particle-based enzyme-linked immunosorbent assay. Urine was collected for JC virus DNA detection. RESULTS: At baseline (n = 1,096), overall anti-JC virus antibody prevalence was 56.0% (95% confidence interval [CI], 53.0-59.0) in STRATIFY-1 patients, with an assay false-negative rate of 2.7% (95% CI, 0.9-6.2). Prevalence was significantly lower in females (53.4%; 95% CI, 49.9-56.8) than males (64.3%; 95% CI, 58.2-70.0) and increased with age, p = 0.0019 and p = 0.0001, respectively. Prevalence was similar in patients regardless of natalizumab exposure or prior immunosuppressant use, p = 0.9709 and p = 0.6632, respectively. STRATIFY-1 results were generally consistent with those observed in another large North American cohort, TYGRIS-US (n = 1,480). INTERPRETATION: Baseline results from STRATIFY-1 are consistent with other studies utilizing this assay that demonstrate a 50 to 60% prevalence of anti-JC virus antibodies, a low false-negative rate, and an association of increasing age and male gender with increasing anti-JC virus antibody prevalence. Neither natalizumab exposure nor prior immunosuppressant use appear to affect prevalence. Longitudinal data from STRATIFY-1 will confirm the stability of anti-JC virus antibody prevalence over time.

Rivaroxaban for thromboprophylaxis in patients undergoing major orthopedic surgery.

OBJECTIVE: To review the pharmacology, pharmacokinetics, and clinical efficacy/safety profile of rivaroxaban to inform health-care professionals of this new agent for the prevention of venous thromboembolism (VTE) in patients undergoing major orthopedic surgery. DATA SOURCES: A literature search was performed in PubMed/MEDLINE (1966-March 2010), International Pharmaceutical Abstracts (1970-March 2010), and EMBASE (1990-March 2010), limited to publications in English, using the search terms BAY 59-7939, rivaroxaban, factor Xa inhibitor, hip replacement, and/or knee replacement to identify literature sources. References from retrieved articles were evaluated to identify relevant literature. Unpublished Phase 3 clinical trials in progress (using www.clinicaltrials.gov) were also reviewed. The Food and Drug Administration, European Medicines Agency, and Health Canada Web sites were used to retrieve product monographs, regulatory guidance, and advisory committee briefing packets. STUDY SELECTION AND DATA EXTRACTION: All available studies relevant to the pharmacology, pharmacokinetics, and clinical safety/efficacy of rivaroxaban for the prevention of VTE in patients undergoing major orthopedic surgery were included, with preference for clinical data. DATA SYNTHESIS: Rivaroxaban use was significantly more effective for thromboprophylaxis in patients undergoing total knee replacement (TKR) or total hip replacement (THR), compared to enoxaparin for the composite incidence of deep vein thrombosis, nonfatal pulmonary embolism, all-cause mortality, and the rate of major VTE; bleeding events occurred at statistically similar rates. In Phase 3 studies, rivaroxaban 10 mg was administered orally 6-8 hours post-surgery and post-hemostasis. Thereafter, administration was once daily for 35 days in THR and 10-14 days in TKR. CONCLUSIONS: Rivaroxaban has demonstrated comparable safety and superior efficacy to the commonly used low-molecular-weight heparin, enoxaparin. Ongoing and future clinical trials will allow clinicians to further assess the efficacy, safety, and pharmacoeconomics of rivaroxaban.

Ustekinumab: treatment of adult moderate-to-severe chronic plaque psoriasis.

OBJECTIVE: To systematically review the pharmacology, pharmacokinetics, clinical efficacy, and safety profile of ustekinumab to inform pharmacists and other healthcare professionals of this new biologic therapy for psoriasis. DATA SOURCES: A search of PubMed/MEDLINE, EMBASE, and International Pharmaceutical Abstracts was performed through July 2009, limited to publications in English, using the search terms CNTO-1275, ustekinumab, interleukin-12, interleukin-23, and/or psoriasis to identify literature sources. References from the retrieved articles were also evaluated to identify relevant literature. An abstract from a Congress of the European Academy of Dermatology and Venereology and unpublished Phase 3 clinical trials in progress (using www.clinicaltrials.gov) were also reviewed. The Food and Drug Administration, European Medicines Agency, and Health Canada Web sites were used to retrieve product monographs, regulatory guidances, and advisory committee briefing packets. STUDY SELECTION AND DATA EXTRACTION: All available studies relevant to the pharmacology, pharmacokinetics, and clinical safety/efficacy of ustekinumab for the treatment of psoriasis were included, with preference for human data. DATA SYNTHESIS: Ustekinumab, an anti-interleukin-12/23 monoclonal antibody, achieved the primary endpoint of 75% reduction in the Psoriasis Area and Severity Index score in a large proportion of patients in the Phase 3 PHOENIX trials. Commensurate improvements were also seen in the Physician's Global Assessment and Dermatology Life Quality Index scores. These efficacy results were reproduced in the ACCEPT trial, demonstrating superiority of ustekinumab to etanercept. The frequency of adverse events was similar between ustekinumab and placebo; common adverse events reported included nasopharyngitis, upper respiratory tract infection, headache, arthralgia, cough, and injection site reactions. Phase 3 studies indicate that the optimal dosing appears to be 45 mg for patients weighing less than 100 kg or 90 mg for patients weighing more than 100 kg, with both doses administered subcutaneously. In these studies, the second dose was given 4 weeks after the first and then every 8-12 weeks thereafter, based upon response. CONCLUSIONS: Ustekinumab, a promising new therapy, reduces the extent and severity of psoriasis and was well tolerated in clinical trials. Ongoing clinical trials will allow clinicians to further assess the efficacy/safety profile of this novel biologic.

Hypoglycemia and clinical outcomes in patients with diabetes hospitalized in the general ward.

OBJECTIVE: Hypoglycemia is associated with adverse outcomes in mixed populations of patients in intensive care units. It is not known whether the same risks exist for diabetic patients who are less severely ill. In this study, we aimed to determine whether hypoglycemic episodes are associated with higher mortality in diabetic patients hospitalized in the general ward. RESEARCH DESIGN AND METHODS: This retrospective cohort study analyzed 4,368 admissions of 2,582 patients with diabetes hospitalized in the general ward of a teaching hospital between January 2003 and August 2004. The associations between the number and severity of hypoglycemic (