Subacute Sclerosing Panencephalitis Therapy
Action And Clinical Pharmacology: Mechanism(s) that might explain the results of the clinical studies employing inosiplex have not been completely elucidated. However, possible antiviral and immunomodulating properties of this drug may be involved.
Serum uric acid concentration rose with increasing inosiplex doses. Hyperuricemic levels (greater than 7.5 mg%) were seen at doses equal to or exceeding 3 g/day. At doses of 4 g/day, about 60% of the subjects had serum uric acid levels in excess of 7 mg%; 30% of the subjects exceeded 7.5 mg%. Urinary uric acid excretion was also elevated after inosiplex administration. The time for urine normalization was usually longer than that required for normalization of serum uric acid level. In 1 case, uricosuria was found to last more than 9 days, and another case was reported in which 3 weeks were required to restore uric acid excretion to normal level.
Inosiplex is composed of inosine and the p-acetamidobenzoic acid salt of N, N-dimethylamido-2-propanol. The principal metabolite (about 80%) of p-acetamidobenzoic acid is O-acylglucuronide and the principal metabolite of N, N-dimethylamine-2-propanol is N, N-dimethylamino- 2-propanol-N-oxide. Virtually 100% of the metabolites was recovered in urine within 8 through 24 hours postadministration period. Each of the compoments of inosiplex is rapidly metabolized, the inosine and p-acetamidobenzoic acid more extensively than N, N-dimethylamino-2-propanol.
Indications And Clinical Uses: May be beneficial in retarding neurological deterioration and prolonging life in patients with slowly progressive subacute sclerosing panencephalitis (SSPE). Inosiplex is not indicated for any condition other than SSPE.
Contra-Indications: None for SSPE patients.
Manufacturers’ Warnings In Clinical States: Because the purine (inosine) moiety of inosiplex is rapidly catabolized to uric acid, resulting in elevations of serum and uric acid, it should be used with care in patients with a history of gout, urolithiasis, nephrolithiasis, or renal dysfunction. Uricosuric agents may be administered to patients with severely elevated serum uric acid levels. Precautions
Precautions: Pregnancy: Specific studies on the effects of inosiplex on animal reproduction have been performed and were negative. However, well-controlled trials concerning fetal risk and impairment of fertility in humans are not available. Therefore, care should be taken in the use of inosiplex by pregnant women and women of childbearing age, and the risks involved should be assessed.
Adverse Reactions: Other than potential problems arising from uric acid metabolism, no adverse physiological reactions have been unequivocally associated with inosiplex therapy.
Symptoms And Treatment Of Overdose: Symptoms and Treatment: Toxic effects from an overdose of inosiplex have not been observed. Since the drug is rapidly metabolized, reduction in dosage or withdrawal from treatment with symptomatic general management of signs and symptoms would generally suffice should any unfoward reaction occur. Similar management would apply to an accidental overdose.
Dosage: Adults and Children: The recommended dosage is 50 mg/kg/day, up to a maxium of 3 g/day, administered orally in 3 to 4 equally divided doses during waking hours.
Availability And Storage: Each white, round, scored tablet contains: inosiplex 500 mg. Nonmedicinal ingredients: magnesium stearate, microcrystalline cellulose, povidone, pregelatinized cornstarch and stearic acid. Tartrazine-free. Amber glass bottles of 100. Store at room temperature.
ISOPRINOSINE® Rivex Pharma Inosiplex Subacute Sclerosing Panencephalitis Therapy