Pharmacy Bulletin

Pharmacy Bulletin

We share important prescription drug information to help you stay informed about updates concerning particular prescription medicines.

VativoRx Bottle update
Indication Extended for Oxlumo
Oxlumo® (lumasiran – Alnylam Pharmaceuticals) was initially approved by the U.S. Food and Drug Administration (FDA) in November 2020, to treat primary hyperoxaluria type 1 (PH1) by lowering urinary oxalate levels. Now, it can be used to decrease oxalate levels in the blood, as well. A group of rare inherited metabolic conditions that affect only a few thousand Americans, PH is caused by too much oxalate in the body. Resulting in kidney damage may lead to end-stage renal disease and kidney failure. Excess oxalate also may affect bones, eyes, heart, skin, and other parts of the body. A small interfering ribonucleic acid (siRNA), Oxlumo blocks the activity of the hydroxy acid oxidase 1 (HAO1) gene, to reduce the amounts of an enzyme needed for oxalate production. Administered by a healthcare provider as a subcutaneous (SC) injection, it is dosed by weight with the first three doses on a monthly schedule, then it is given once every three months. For its complete prescribing information, check here.

Pediatric Indication Approved for Firdapse
On Sept. 29, 2022, the FDA approved Firdapse® (amifampridine – Catalyst Pharmaceuticals) tablets for treating patients as young as six years old. First approved for adults in 2018, Firdapse is indicated to treat Lambert-Eaton myasthenic syndrome (LEMS), an autoimmune disease that interrupts the flow of nerve impulses to muscles. One result is fatigue and weakness, especially in the legs. LEMS has been diagnosed in only about 400 Americans, mostly adults. Firdapse blocks potassium channels to keep calcium channels open longer, which enhances nerve transmissions. The pediatric dose of Firdapse is weight-based. For children weighing less than 45kg (about 100 pounds) doses start at a total of 5mg to 15mg/day, and increase by 2.5mg/day once every three or four days, if necessary, to a maximum of 40mg/day. All adults and children who weigh 45kg or more begin at a total of 15mg to 30mg per day and increase by 5mg/day every three or four days, to an upper limit of 80mg daily, if lower doses are not effective. All daily totals should be divided into three or four equal parts. Firdapse should not be used for patients who have or ever have had seizures. Here is its most current prescribing information.  

Trogarzo Receives Approval for New Dosage Form
Theratechnologies and TaiMed Biologics’ Trogarzo® (ibalizumab-uiyk) is used along with other antiretroviral therapies to treat human immunodeficiency virus type 1 (HIV-1) infection for adults who have multidrug-resistant (MDR) HIV-1 that has been treated repeatedly, but that is no longer responding to current therapy. According to, approximately 1.2 million Americans have HIV-1, and as many as 25,000 have cases that are MDR. Around one-half of patients who have MDR HIV-1 are not responding to their present antiretroviral regimens. A novel CD4-directed post-attachment HIV-1 inhibitor, Trogarzo works by preventing HIV from infecting CD4+ immune cells to reduce the amount of HIV in the body. It is administered as an intravenous (IV) infusion in a single loading dose of 2,000mg followed by 800mg infusions lasting at least 15 minutes once every two weeks. A new IV push dosage form approved by the FDA on Oct. 3, 2022, will allow the maintenance doses to be delivered in less than one minute, greatly improving convenience for patients. No information is available about possible costs or a market introduction date. Updated prescribing information is here.  

Generics for Myrbetriq
At least two companies, including Zydus Pharmaceuticals, received FDA approval in late September 2022, to market generics for Myrbetriq® (mirabegron – Astellas Pharma) extended-release tablets in both of its strengths – 25mg and 50mg. Mirabegron is a beta3 adrenergic agonist indicated to relieve symptoms of urgency, urinary frequency, and urge urinary incontinence that is associated with overactive bladder (OAB). Taken once a day, it can be used alone or with another drug, solifenacin succinate, which works differently to control OAB. Patients taking mirabegron should have frequent checks of blood pressure because it may cause increases. Settlement agreements may delay some launches until 2024 and no company has announced a release date or pricing information. However, some companies state they will share a 180-day exclusivity period. According to information from IQVIA, U.S. sales for Myrbetriq are about $2.4 billion each year.  

Prezista Generic Approved
Lupin also has disclosed that it received FDA approval on Sept. 29, 2022, for two strengths of its generic to Prezista® (darunavir) tablets. It will have exclusivity for 180 days after the launch date for the 800mg tablets and believes that it will share exclusivity with as yet unidentified other companies for the 600mg strength. Darunavir is a protease inhibitor taken once a day along with food and ritonavir, another protease inhibitor that boosts the effects of darunavir, for treating patients at least three years old who have HIV. Baseline liver enzyme levels need to be established before beginning darunavir and then monitored for elevations during its use. Lupin has not announced a release date or the cost for its darunavir tablets. No generic is available for Prezista oral suspension or for its 75mg and 150mg tablet strengths. Estimated annual sales through the 12 months ending June 30, 2022, for 600mg and 800mg Prezista tablets were $343 million in the U.S.  

MedWatch Update
The FDA issued a safety communication for Evusheld™ (tixagevimab with cilgavimab) on Oct. 3, 2022. It is the only drug that has an emergency use authorization (EUA) to prevent COVID-19 infections for patients who are at least 12 years old and who weigh at least 40kg (88 pounds). Eligible patients have not been exposed to COVID, but they either continue to be at high risk of getting it due to an immunocompromising condition even after being vaccinated or they cannot be fully vaccinated against COVID because of severe side effects from the vaccines or ingredients in them. It is administered as intramuscular (IM) injections once every six months. The FDA is warning that Evusheld is not particularly effective against some of the currently circulating variants of COVID, especially emerging Omicron versions. Patients are advised to test for COVID if they begin to have symptoms, to inform their doctors, and to start treatment with Paxlovid™ (nirmatrelvir tablets; ritonavir tablets – Pfizer) or another COVID treatment as soon as possible if they test positive. More information is in this FDA notice, Evusheld’s Fact Sheet for Healthcare Providers, and its Fact Sheet for Patients and Caregivers.  

On Sept. 29, 2022, Golden State Medical Supply recalled one lot (GS046745) of atenolol tablets, 25mg (NDC# 60429-027-10) and clopidogrel tablets, 75mg (NDC# 51407-0032-10) in 1,000 count bottles. One bottle labeled atenolol, a high blood pressure drug, actually contained the platelet inhibitor, clopidogrel. The risk of serious effects from substituting atenolol for clopidogrel is small, but suddenly stopping atenolol could result in serious adverse cardiovascular (CV) events. Please look here for more information.