Videx Ec Information
Videx ec (Didanosine) Indications And Usage
Videx ec (Didanosine) (didanosine, USP), also known as ddI, in combination with other antiretroviral agents is indicated for the treatment of human immunodeficiency virus (HIV)-1 infection [].
Videx ec (Didanosine) Dosage And Administration
Videx ec (Didanosine) should be administered on an empty stomach. Videx ec (Didanosine) Delayed-Release Capsules should be swallowed intact.
The recommended total daily dose is based on body weight and is administered as one capsule given on a once-daily schedule as outlined in .
The recommended total daily dose to be administered once daily to pediatric patients weighing at least 20 kg who can swallow capsules is based on body weight (kg), consistent with the recommended adult dosing guidelines (see ). Please consult the complete prescribing information for VIDEX (didanosine) Pediatric Powder for Oral Solution for dosage and administration of didanosine to pediatric patients weighing less than 20 kg or who can not swallow capsules.
Videx ec (Didanosine) Dosage Forms And Strengths
VIDEX EC (didanosine, USP) Delayed-Release Capsules are white, opaque capsules as described below:
Videx ec (Didanosine) Contraindications
These recommendations are based on either drug interaction studies or observed clinical toxicities.
Videx ec (Didanosine) Warnings And Precautions
Fatal and nonfatal pancreatitis has occurred during therapy with didanosine used alone or in combination regimens in both treatment-naive and treatment-experienced patients, regardless of degree of immunosuppression. Videx ec (Didanosine) should be suspended in patients with signs or symptoms of pancreatitis and discontinued in patients with confirmed pancreatitis. Patients treated with Videx ec (Didanosine) in combination with stavudine may be at increased risk for pancreatitis.
When treatment with life-sustaining drugs known to cause pancreatic toxicity is required, suspension of Videx ec (Didanosine) therapy is recommended. In patients with risk factors for pancreatitis, Videx ec (Didanosine) should be used with extreme caution and only if clearly indicated. Patients with advanced HIV-1 infection, especially the elderly, are at increased risk of pancreatitis and should be followed closely. Patients with renal impairment may be at greater risk for pancreatitis if treated without dose adjustment. The frequency of pancreatitis is dose related. [.]
Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogues alone or in combination, including didanosine and other antiretrovirals.
see Use in Specific Populations
The safety and efficacy of Videx ec (Didanosine) have not been established in HIV-infected patients with significant underlying liver disease. During combination antiretroviral therapy, patients with preexisting liver dysfunction, including chronic active hepatitis, have an increased frequency of liver function abnormalities, including severe and potentially fatal hepatic adverse events, and should be monitored according to standard practice. If there is evidence of worsening liver disease in such patients, interruption or discontinuation of treatment must be considered.
Hepatotoxicity and hepatic failure resulting in death were reported during postmarketing surveillance in HIV-infected patients treated with hydroxyurea and other antiretroviral agents. Fatal hepatic events were reported most often in patients treated with the combination of hydroxyurea, didanosine, and stavudine. This combination should be avoided. [.]
Postmarketing cases of non-cirrhotic portal hypertension have been reported, including cases leading to liver transplantation or death. Cases of didanosine-associated non-cirrhotic portal hypertension were confirmed by liver biopsy in patients with no evidence of viral hepatitis. Onset of signs and symptoms ranged from months to years after start of didanosine therapy. Common presenting features included elevated liver enzymes, esophageal varices, hematemesis, ascites, and splenomegaly.
Patients receiving Videx ec (Didanosine) should be monitored for early signs of portal hypertension (eg, thrombocytopenia and splenomegaly) during routine medical visits. Appropriate laboratory testing including liver enzymes, serum bilirubin, albumin, complete blood count, and international normalized ratio (INR) and ultrasonography should be considered. Videx ec (Didanosine) should be discontinued in patients with evidence of non-cirrhotic portal hypertension.
Immune reconstitution syndrome has been reported in patients treated with combination antiretroviral therapy, including Videx ec (Didanosine) . During the initial phase of combination antiretroviral treatment, patients whose immune system responds may develop an inflammatory response to indolent or residual opportunistic infections (such as infection, cytomegalovirus, pneumonia [PCP], or tuberculosis), which may necessitate further evaluation and treatment.
Autoimmune disorders (such as Graves’ disease, polymyositis, and Guillain-Barré syndrome) have also been reported to occur in the setting of immune reconstitution; however, the time to onset is more variable, and can occur many months after initiation of treatment.
Videx ec (Didanosine) Adverse Reactions
The following adverse reactions are discussed in greater detail in other sections:
Videx ec (Didanosine) Drug Interactions
Clinical recommendations based on the results of drug interaction studies are listed in . Pharmacokinetic results of drug interaction studies are shown in - [].
Exposure to didanosine is increased when coadministered with tenofovir disoproxil fumarate [ and ]. Increased exposure may cause or worsen didanosine-related clinical toxicities, including pancreatitis, symptomatic hyperlactatemia/lactic acidosis, and peripheral neuropathy. Coadministration of tenofovir disoproxil fumarate with Videx ec (Didanosine) should be undertaken with caution, and patients should be monitored closely for didanosine-related toxicities and clinical response. Videx ec (Didanosine) should be suspended if signs or symptoms of pancreatitis, symptomatic hyperlactatemia, or lactic acidosis develop []. Suppression of CD4 cell counts has been observed in patients receiving tenofovir disoproxil fumarate with didanosine at a dose of 400 mg daily.
Videx ec (Didanosine) Use In Specific Populations
The Centers for Disease Control and Prevention recommend that HIV-infected mothers not breastfeed their infants to avoid risking postnatal transmission of HIV.
mothers should be instructed not to breastfeed if they are receiving didanosine
Videx ec (Didanosine) Overdosage
There is no known antidote for didanosine overdosage. In phase 1 studies, in which buffered formulations of didanosine were initially administered at doses ten times the currently recommended dose, toxicities included: pancreatitis, peripheral neuropathy, diarrhea, hyperuricemia, and hepatic dysfunction. Didanosine is not dialyzable by peritoneal dialysis, although there is some clearance by hemodialysis [].
Videx ec (Didanosine) Description
Videx ec (Didanosine) is the brand name for an enteric-coated formulation of didanosine, USP, a synthetic purine nucleoside analogue active against HIV-1. Videx ec (Didanosine) Delayed-Release Capsules, containing enteric-coated beadlets, are available for oral administration in strengths of 125, 200, 250, and 400 mg of didanosine. The inactive ingredients in the beadlets include carboxymethylcellulose sodium 12, diethyl phthalate, methacrylic acid copolymer, sodium hydroxide, sodium starch glycolate, and talc. The capsule shells contain gelatin and titanium dioxide. The capsules are imprinted with edible inks.
Didanosine is also available in a powder formulation. Please consult the prescribing information for VIDEX (didanosine) Pediatric Powder for Oral Solution for additional information.
The chemical name for didanosine is 2′,3′-dideoxyinosine. The structural formula is:
Didanosine is a white crystalline powder with the molecular formula CHNO and a molecular weight of 236.2. The aqueous solubility of didanosine at 25° C and pH of approximately 6 is 27.3 mg/mL. Didanosine is unstable in acidic solutions. For example, at pH less than 3 and 37° C, 10% of didanosine decomposes to hypoxanthine in less than 2 minutes. In Videx ec (Didanosine) , an enteric coating is used to protect didanosine from degradation by stomach acid.
Videx ec (Didanosine) Nonclinical Toxicology
Lifetime carcinogenicity studies were conducted in mice and rats for 22 and 24 months, respectively. In the mouse study, initial doses of 120, 800, and 1200 mg/kg/day for each sex were lowered after 8 months to 120, 210, and 210 mg/kg/day for females and 120, 300, and 600 mg/kg/day for males. The two higher doses exceeded the maximally tolerated dose in females and the high dose exceeded the maximally tolerated dose in males. The low dose in females represented 0.68-fold maximum human exposure and the intermediate dose in males represented 1.7-fold maximum human exposure based on relative AUC comparisons. In the rat study, initial doses were 100, 250, and 1000 mg/kg/day, and the high dose was lowered to 500 mg/kg/day after 18 months. The upper dose in male and female rats represented 3-fold maximum human exposure.
Didanosine induced no significant increase in neoplastic lesions in mice or rats at maximally tolerated doses.
Didanosine was positive in the following genetic toxicology assays: 1) the tester strain WP2 uvrA bacterial mutagenicity assay; 2) the L5178Y/TK+/- mouse lymphoma mammalian cell gene mutation assay; 3) the chromosomal aberrations assay in cultured human peripheral lymphocytes; 4) the chromosomal aberrations assay in Chinese Hamster Lung cells; and 5) the BALB/c 3T3 transformation assay. No evidence of mutagenicity was observed in an Ames bacterial mutagenicity assay or in rat and mouse micronucleus assays.
Videx ec (Didanosine) How Supplied/storage And Handling
VIDEX EC (didanosine, USP) Delayed-Release Capsules are white, opaque capsules that are packaged in bottles with child-resistant closures as described in .
Videx ec (Didanosine) Patient Counseling Information
See .
Patients should be informed that when didanosine is used in combination with other agents with similar toxicities, the incidence of adverse events may be higher than when didanosine is used alone. These patients should be followed closely.
Patients should be cautioned about the use of medications or other substances, including alcohol, which may exacerbate Videx ec (Didanosine) toxicities.
Videx ec (Didanosine) is not a cure for HIV-1 infection, and patients may continue to experience illnesses associated with HIV-1 infection, including opportunistic infections. Therefore, patients should remain under the care of a physician when using Videx ec (Didanosine) .
Patients should be advised to avoid doing things that can spread HIV-1 infection to others.
Patients should be instructed to swallow the capsule as a whole and to not open the capsule.
Patients should be instructed to not miss a dose but if they do, patients should take Videx ec (Didanosine) as soon as possible. Patients should be told that if it is almost time for the next dose, they should skip the missed dose and continue with the regular dosing schedule.
Patients should be instructed to contact a poison control center or emergency room right away in case of an overdose.
Videx ec (Didanosine)
Videx ec (Didanosine)
Videx ec (Didanosine)
Videx ec (Didanosine)
Videx ec (Didanosine)
