Efavirenz

Common name: Efavirenz tablets

Trade name: Stolonin

All names: Efavirenz, Stolonin, Efavirenz tablets, Efavirenz, EFV

Indications:

This product is suitable for the treatment of adults, adolescents and children infected with HIV-1 in combination with other antiviral drugs.

Usage and dosage:

Oral administration: for HIV infection, 600 mg each time, once a day.

Children under 3 years old take 200-400mg each time, children over 3 years old take 600mg each time, once a day.

Those who have adverse reactions to the initial treatment but need to maintain treatment can take it before bedtime.

Adverse Reactions:

The most common adverse events that were at least moderate to severe were rash, dizziness, nausea, headache, and fatigue.

The most notable adverse events associated with this product are rash and neurological symptoms.

Some other less common treatment-related adverse events in clinical studies include: allergic reactions, coordination disorders, ataxia, confusion, coma, dizziness, vomiting, diarrhea, hepatitis, difficulty concentrating, insomnia, anxiety, strange dreams, drowsiness, depression, abnormal thinking, excitement, amnesia, confusion, emotional lability, euphoria, hallucinations and psychiatric symptoms.

In addition, some adverse events reported in post-marketing surveillance include: neurasthenia, paranoia, cerebellar coordination and balance disorders, convulsions, pruritus, abdominal pain, blurred vision, flushing, gynecomastia, liver failure, photosensitivity dermatitis, pancreatitis and redistribution or accumulation of body fat in the back of the neck, breasts, abdomen and retroperitoneum, tinnitus and tremor.

Except for the higher incidence and severity of rash, the types and incidence of other adverse reactions in children are basically similar to those in adults.

Contraindications:

This product is contraindicated in patients who are clinically allergic to any ingredient of this product.

This product should not be used concomitantly with terfenadine, astemizole, cisapride, midazolam, triazolam, pimozide, bepridil, or ergot derivatives because competition of efavirenz for CYP3A4 may inhibit the metabolism of these drugs and may cause serious and/or life-threatening adverse events [e.g., cardiac arrhythmias, sustained sedation, or respiratory depression].

This product should not be used in combination with standard doses of voriconazole. Because efavirenz can significantly reduce the plasma concentration of voriconazole, voriconazole also significantly increases the plasma concentration of efavirenz.

Note:

This product must not be used alone for HIV treatment or as a single drug added to an ineffective treatment plan. Physicians should consult the appropriate manufacturer's product Medication Guide when prescribing drugs for use with this product. If any antiretroviral agent in the combination regimen is discontinued due to suspected intolerance, discontinuation of all antiretroviral agents should be carefully considered. Combination antiretroviral therapy should be restarted while symptoms of intolerance resolve. Intermittent monotherapy with antiretroviral drugs and sequential re-administration of antiretroviral drugs is not advisable because it increases the likelihood of the development of selected resistant mutant viruses.

It is not recommended to include efavirenz in products co-administered with Stolonin (e.g. ATRIPIA). Fetal abnormalities have been observed in animals given efavirenz. Therefore, women taking this product should avoid becoming pregnant. Condoms should be used in conjunction with other contraceptive methods (eg, oral contraceptives or other hormonal contraceptives).

Rash: Mild to moderate rash was reported in clinical trials with this product and usually resolved with continued treatment. Appropriate antihistamines and/or corticosteroids may improve tolerance and accelerate rash resolution. Severe rash with blistering, moist scaling, or ulceration has been reported in less than 1% of patients treated with this product. The incidence of erythema multiforme or Stevens-Johnson syndrome is 0.14%. Patients who develop severe rash with blistering, scaling, involvement of mucous membranes, or fever should discontinue use of this product. If treatment with this product is interrupted, discontinuation of other antiretroviral drugs should also be considered to avoid the development of drug-resistant viruses. Rashes were reported in 26 (46%) of 57 children treated with this product, and severe rashes were reported in 3 children (5%). Appropriate antihistamine prophylaxis may be considered before initiating treatment with this product in children.

Psychiatric symptoms: Adverse psychiatric events have been reported in patients treated with this product. Patients with previous psychiatric disorders appear to be at higher risk of developing psychiatric symptoms. Post-marketing adverse events include individual reports of suicide, delusions, and abnormal behavior, but it cannot be concluded from these reports whether these conditions are related to this product. Patients are advised to contact their doctor immediately once the above symptoms occur to determine whether these symptoms are related to this product. If so, further evaluate whether the risks of continuing to take the drug outweigh the benefits.

Nervous system symptoms: In clinical studies, patients who were treated with 600 mg of this product orally every day often experienced relatively uncomfortable neurological symptoms, including dizziness, insomnia, drowsiness, inability to concentrate and strange dreams, but are not limited to these. Neurologic symptoms usually appear within the first one to two days of treatment and generally resolve after two to four weeks. Patients should be informed that if these symptoms occur, continued treatment will usually improve them and does not predict the development of any rare psychiatric symptoms.

Convulsions: Convulsive attacks are rare in patients taking efavirenz and are usually associated with a known history of seizures. Patients concurrently taking anticonvulsant drugs that are primarily metabolized by the liver, such as phenytoin, carbamazepine, and phenobarbital, require regular monitoring of their plasma concentrations. In a drug interaction study, carbamazepine plasma concentrations were decreased when coadministered with efavirenz. Medication should be used with caution in patients with a history of convulsions.

Food effects: Taking efavirenz with food will increase the exposure of efavirenz and increase the occurrence of adverse reactions. This adverse reaction occurs more frequently when taking the tablets than when taking the hard capsules. Therefore, taking this product before going to bed is the recommended way of taking it. Immune Reconstitution Syndrome: Immune reconstitution syndrome has been reported in patients receiving combination antiretroviral therapy (CART) including CART. Early in treatment, patients whose immune systems respond to CART may have an increased inflammatory response to asymptomatic or residual opportunistic infections, which requires further evaluation and treatment.

Special groups: Because the metabolism of efavirenz is mediated by cytochrome P450, and there is limited clinical experience in using this drug in patients with chronic liver disease, this product should be used with caution in patients with liver disease. The risk of serious and potentially fatal hepatic adverse events is significantly increased in patients with chronic hepatitis B or C treated with combination antiretroviral drugs. The pharmacokinetics of efavirenz have not been studied in patients with renal impairment; since less than 1% of efavirenz is excreted unchanged in the urine, impaired renal function has minimal impact on the elimination of efavirenz. The number of older patients evaluated in clinical studies was too small to determine whether they respond differently to this drug than younger patients. This product has not been evaluated in children under 3 years of age or weighing less than 13 kg. There is evidence that efavirenz may alter the pharmacokinetics of efavirenz in very young children. For this reason, efavirenz should not be given to children under 3 years of age.

Liver enzymes: Monitoring of liver enzymes is recommended in patients with a known or suspected history of hepatitis B or C and in patients treated with other hepatotoxic drugs. For patients with persistent elevations in serum aminotransferases greater than 5 times the upper limit of the normal range, the benefits of continued treatment with this product need to be weighed against the unknown risk of severe hepatotoxicity.

Storage:

Shield and seal.

Mechanism of action:

Efavirenz is a selective non-nucleoside reverse transcriptase inhibitor of human immunodeficiency virus type 1 (HIV-1). Efavirenz is a non-competitive inhibitor of HIV-1 reverse transcriptase (RT), acting on templates, primers or nucleoside triphosphates, and has a small amount of competitive inhibition.

Safety and efficacy:

To compare the clinical efficacy of nevirapine and efavirenz in the treatment of AIDS. 100 AIDS patients were selected and randomly divided into nevirapine group and efavirenz group, with 50 cases in each group. The nevirapine group was treated with nevirapine, and the efavirenz group was treated with efavirenz. The immunological efficacy, virological efficacy and occurrence of adverse reactions were compared between the two groups of patients. Results: There was no statistically significant difference in CD4+ cell counts between the two groups at baseline and 48, 96, and 144 weeks of treatment (P>0.05). The CD4+ cell counts of the two groups of patients at 96 and 144 weeks of treatment were higher than those at 48 weeks of treatment (P0.05); the CD4+ cell counts of the two groups of patients at 144 weeks of treatment were higher than those at 96 weeks (P0.05). At 48, 96 and 144 weeks of treatment, there was no statistically significant difference in the proportion of patients in the two groups with a viral load of 50 copies/ml (P0.05). The incidence of gastrointestinal symptoms, abnormal liver function, and rash in the patients in the Wellen group was lower than that in the Nevirapine group, and the incidence of central nervous system symptoms was higher than that in the Nevirapine group (P0.05). There was no statistically significant difference in the incidence of dyslipidemia between the two groups (P0.05). Conclusion Both nevirapine and efavirenz can achieve good clinical efficacy in the treatment of AIDS.