The prolonged sedation from lorazepam may, however, be an acceptable trade-off for its reliable duration of effects, particularly if the person needs to be transferred to another facility. Although lorazepam is not necessarily better than diazepam at initially terminating seizures, lorazepam is, nevertheless, replacing diazepam as the intravenous agent of choice in status epilepticus.Lorazepam serum levels are proportional to the dose administered. Giving 2 mg oral lorazepam will result in a peak total serum level of around 20 ng/mL around two hours later, half of which is lorazepam, half its inactive metabolite, lorazepam-glucuronide. A similar lorazepam dose given intravenously will result in an earlier and higher peak serum level, with a higher relative proportion of unmetabolised (active) lorazepam. On regular administration, maximum serum levels are attained after three days. Longer-term use, up to six months, does not result in further accumulation. On discontinuation, lorazepam serum levels become negligible after three days and undetectable after about a week. Lorazepam is metabolized in the liver by conjugation into inactive lorazepam-glucuronide. This metabolism does not involve liver oxidation, so is relatively unaffected by reduced liver function. Lorazepam-glucuronide is more water-soluble than its precursor, so gets more widely distributed in the body, leading to a longer half-life than lorazepam. Lorazepam-glucuronide is eventually excreted by the kidneys, and, because of its tissue accumulation, it remains detectable, particularly in the urine, for substantially longer than lorazepam. Pharmacodynamics
Relative to other benzodiazepines, lorazepam is thought to have high affinity for GABA receptors, which may also explain its marked amnesic effects.
Givosiran, sold under the brand name Givlaari, is a medication used for the treatment of adults with acute hepatic porphyria. Givosiran is a small interfering RNA (siRNA) directed towards delta-aminolevulinate synthase 1 (ALAS1), an important enzyme in the production of heme. The most common side effects include nausea and injection site reactions.The U.S. Food and Drug Administration (FDA) considers it to be a first-in-class medication. Medical uses
Givosiran is indicated for the treatment of adults with acute hepatic porphyria, a genetic disorder resulting in the buildup of toxic porphyrin molecules which are formed during the production of heme (which helps bind oxygen in the blood). History
In November 2019, givosiran was approved in the United States for the treatment of adults with acute hepatic porphyria (AHP).Efficacy was evaluated in ENVISION (NCT03338816), a randomized, double‑blind, placebo‑controlled, multinational trial enrolling 94 participants with acute hepatic porphyria. Participants were randomized (1:1) to receive once monthly subcutaneous injections of givosiran 2.5 mg/kg or placebo during a six‑month double‑blind period. The performance of givosiran was measured by the rate of porphyria attacks that required hospitalizations, urgent health care visits or intravenous infusion of hemin at home. Participants who received givosiran experienced 70% fewer porphyria attacks compared to patients receiving a placebo.The U.S. Food and Drug Administration (FDA) granted the application for givosiran breakthrough therapy designation, priority review designation, and orphan drug designation. The FDA granted the approval of Givlaari to Alnylam Pharmaceuticals. References
External links
"Givosiran". Drug Information Portal. U.S. National Library of Medicine (NLM).