482 Solriamfetol Titration & AdministRaTion (START): dosing and titration strategies in patients with narcolepsy starting solriamfetol

Introduction Solriamfetol (Sunosi®), a dopamine/norepinephrine reuptake inhibitor, is approved (US and EU) to treat excessive daytime sleepiness (EDS) in adults with narcolepsy (75–150 mg/day) or obstructive sleep apnea (OSA) (37.5–150 mg/day). Previous research examined the use of solriamfetol in clinical trial settings but research in real-world settings was not previously conducted. This study characterized real-world dosing and titration with solriamfetol. Methods This virtual, descriptive study included a quantitative retrospective patient chart review among US-based physicians prescribing solriamfetol. Target enrollment was 25 physicians treating patients with EDS associated with OSA or narcolepsy. Titration strategies were classified as de novo (no prior EDS medication), transition (switched/switching from existing EDS medications onto solriamfetol), or add-on (adding solriamfetol to current EDS medication). Results Twenty-six physicians participated. Seventy patients with narcolepsy were analyzed (type 1, n=24; type 2, n=46; mean±SD age, 40±11 years; 57% female; 6 also had OSA); EDS was primarily moderate (59%) or severe (36%). Solriamfetol initiation was de novo for 19 (27%) patients, transition for 31 (44%), and add-on for 20 (29%). Most patients (86%) started solriamfetol at 75 mg; 11% and 3% started at 37.5 mg and 150 mg, respectively. The final/stable dose was 150 mg for 76% (53/70) of patients and 75 mg for 24% (17/70). Most patients (67%) had 1 dose adjustment to reach their final dose; 4% had 2 adjustments, 4% had 3 adjustments, and 24% had none. Mean±SD time to reach a stable dose was 15.1±11.8 days overall, 19.4±9.3 days with de novo treatment, 15.0±13.7 days for transition, and 11.9±8.6 days for add-on. Physicians most frequently considered EDS severity (44% of patients) when titrating. Among patients transitioning, 14/22 (64%) taking a wake-promoting agent (WPA) discontinued it abruptly while 5/9 (56%) taking a stimulant were tapered off. Physicians were overall likely (n=33, 47%) or very likely (n=30, 43%) to recommend their approach for similar patients. Conclusion In a real-world study, the majority of physicians prescribing solriamfetol for patients with narcolepsy started at the 75-mg dose, tapered stimulants but abruptly discontinued WPAs, and made 1 adjustment to reach a stable dose across 15 days on average. Support (if any) Jazz Pharmaceuticals

Magnesium-induced ketamine toxicity

A 62-year-old man with metastatic duodenal cancer was admitted to a hospice for a trial of ketamine to manage complex neuropathic abdominal pain. The patient was incrementally established on a dose of 150 mg orally four times day with no adverse effects. Following treatment of hypomagnesaemia intravenously, the patient experienced marked symptoms of ketamine toxicity, known as a ‘K-hole’ amongst recreational users, following the next dose of ketamine. Ketamine and magnesium are both antagonists of the N-methyl-D-aspartate receptor, which plays a part in central sensitisation to pain. There is some evidence that correction of hypomagnesaemia may improve analgesia and that there is synergism between ketamine and magnesium in analgesia, but this relationship is poorly understood. This is the first report suggesting that blood magnesium levels may affect the side effects of a stable dose of ketamine.

Ixekizumab, with or without concomitant methotrexate, improves signs and symptoms of PsA: week 52 results from Spirit-P1 and Spirit-P2 studies

Background The efficacy and safety of ixekizumab (IXE) with and without continuous concomitant methotrexate (MTX), for up to 52 weeks of treatment, were evaluated in patients with active psoriatic arthritis (PsA). Methods Patients with active PsA who were biologic-naive (SPIRIT-P1) or had prior inadequate response to tumor necrosis factor inhibitors (SPIRIT-P2) were randomized to 80 mg IXE every 4 (IXE Q4W) or 2 weeks (IXE Q2W), after a 160-mg initial dose. In this post hoc analysis, efficacy and safety were assessed up to week 52 in the subgroups of patients who received (i) IXE as monotherapy and (ii) IXE along with a stable dose of MTX (no dose tapering or increase). Efficacy outcomes included, but were not limited to, the percentage of patients achieving the American College of Rheumatology (ACR) responses. Results Out of 455 patients initially randomized to IXE, 177 (38.9%) received monotherapy, 230 (50.5%) had concomitant MTX use, and 48 (10.5%) had other concomitant medication. Overall, 183 (40.2%) received IXE with a stable dose of concomitant MTX for 1 year. At week 52, the percentage of patients achieving ACR20/50/70 responses in IXE Q4W monotherapy versus concomitant MTX groups were 66.3% versus 55.3%, 48.4% versus 38.8%, and 35.8% versus 27.1%, respectively; these responses were generally similar with IXE Q2W. The safety profiles were similar between patients receiving IXE with or without concomitant MTX. Conclusions In this post hoc analysis, treatment with IXE demonstrated sustained efficacy in patients with PsA up to 1 year of treatment, with or without concomitant MTX therapy. Trial registration ClinicalTrials.gov NCT01695239 and NCT02349295.

Ixekizumab, With Or Without Concomitant Methotrexate, Improves Signs And Symptoms Of Psa: Week 52 Results From Spirit-P1 And Spirit-P2 Studies

Background: The efficacy and safety of ixekizumab (IXE) with and without continuous concomitant methotrexate (MTX), for up to 52 weeks of treatment, was evaluated in patients with active psoriatic arthritis (PsA). Methods: Patients with active PsA who were biologic-naive (SPIRIT-P1) or had prior inadequate response to tumor necrosis factor inhibitors (SPIRIT-P2), were randomized to 80 mg IXE every 4 (IXE Q4W) or 2 weeks (IXE Q2W), after a 160-mg initial dose. In this post-hoc analysis, efficacy and safety were assessed up to Week 52 in the subgroups of patients who received: (i) IXE as monotherapy and (ii) IXE along with a stable dose of MTX (no dose tapering or increase). Efficacy outcomes included, but were not limited to, the percentage of patients achieving American College of Rheumatology (ACR) responses.Results: Out of 455 patients initially randomized to IXE, 177 (38.9%) received monotherapy, 230 (50.5%) had concomitant MTX use, and 48 (10.5%) had other concomitant medication. Overall, 183 (40.2%) received IXE with a stable dose of concomitant MTX for 1 year. At Week 52, the percentage of patients achieving ACR20/50/70 responses in IXE Q4W monotherapy versus concomitant MTX groups were 66.3% versus 55.3%, 48.4% versus 38.8%, and 35.8% versus 27.1%, respectively; these responses were generally similar with IXE Q2W. The safety profiles were similar between patients receiving IXE with or without concomitant MTX.Conclusions: In this post-hoc analysis, treatment with IXE demonstrated sustained efficacy in patients with PsA up to 1 year of treatment, with or without concomitant MTX therapy.Trial registration: ClinicalTrials.gov NCT01695239 and NCT02349295