Obnyx 40mg (Enzalutamide)
Enzalutamide is an active ingredient of Obnyx 40mg tablets available in the strength of 40mg. Obnyx 40mg tablets are used to treat the metastatic prostate cancer, in men. Obnyx 40mg is exhibits its action by stopping the advancement of tumor cells by blockade of androgen hormones especially testosterone.
Obnyx 40mg containing Enzalutamide is also categorized as an anti-androgen chemo medicine. Obnyx 40mg is not self medication; it is used under the knowledge of medical oncologist.
Obnyx 40mg tablets are prescribing for; Metastatic or long lasting castration resistant prostate cancer
MECHANISM OF ACTION
Obnyx 40mg containing anti-androgen agent like Enzalutamide, it expels an anti-tumor activity in different steps. Obnyx 40mg tablets are interfere in androgen receptor signaling pathway, which prohibiting androgen binding to androgen receptors leads to androgen receptor nuclear translocation inhibition and interact with DNA. The major metabolite of Obnyx 40mg is N-desmethyl Enzalutamide which is similar to Enzalutamide activity. The anti-tumor activity of Obnyx 40mg is exposed by depleting the multiplication and persuades cell lysis in prostate cancer cells.
The peak plasma concentration time of Obnyx 40mg occurs at 1 hour with the range of 0.5 to 3 hours). The steady state of Obnyx 40mg occurs in day 28. The volume of distribution occur after single dose of Obnyx 40mg is 110L Obnyx 40mg has highly bounds to the human plasma protein with the range of 97 to 98%.
The major metabolite of Enzalutamide is N-desmethyl Enzalutamide has 95% bound to human plasma protein. The most important isoenzymes responsible for the metabolism of Enzalutamide are CYP2C8 & CYP3A4. CYP2C8 is involved in the formation of an active metabolite N-desmethyl Enzalutamide. Obnyx 40mg is majorly excreted through liver metabolism, 71% of metabolite present in urine and 14% in feces. The terminal half life period of Obnyx 40mg tablet is occurs after a single dose at 5.8days and N-desmethyl Enzalutamide is taken 7.8 to 8.6 days.
The usual recommended dosage of Obnyx 40mg is 160mg, but available strength of Obnyx 40mg Four tablets of Obnyx 40mg should be taken at a time as a single dose. Obnyx 40mg tablet should be administered with or without food.
Dosing alteration: In ≥ grade 3 toxicity or extreme side effects: Postpone the dose of Obnyx 40mg for 1 week or as far as symptoms progress to ≤ grade 2, continue at the same or reduced to 120mg or 80mg. Concurrent use with strong CYP2C8 inhibitors:
In case of combination with strong CYP2C8 inhibitors, diminish the dose of Obnyx 40mg to 80mg as a single dose. Concurrent use with strong CYP3A4 inducers: In case of combination with strong CYP3A4 inducers, increasing the dose of Obnyx 160mg to 240mg as a single dose.
The major adverse effect during the therapy of Obnyx 40mg tablets are;
Seizure may produce during the treatment with Obnyx 40mg tablets, if seizure occurs the treatment should be discontinued until seizure resolved. To avoid this condition, patient should be counsel about the problems occurred during the therapy before starting the treatment. Seizure may leads to loss of consciousness.
POSTERIOR REVERSIBLE ENCEPHALOPATHY SYNDROME PRES
Patient who are all taking Obnyx 40mg tablets acquired PRES, is a neurological problem produce symptoms like headache, lethargy, confusion, loss of vision, other neurological problems related with hypertension. PRES diagnosed by MRI. If patient acquired with PRES, discontinue the Obnyx 40mg therapy
OBNYX 40MG40MG TABLETS CAUSING SIDE EFFECT
Asthenia Peripheral edema Back pain, arthralgia Musculoskeletal pain Muscular weakness Musculoskeletal stiffness Diarrhea Hot flush Hypertension Headache Dizziness Spinal cord compression Caude equine syndrome Paresthesia Mental disorders Hypoesthesia Respiratory tract infections Insomnia Anxiety Hematuria Pollakiuria Non pathologic fractures Pruritus Dry skin Epistaxis
Obnyx 40mg tablets concomitant with strong CYP2C8 inhibitors like gemfibrozil which may increase the plasma concentration time curve of Enzalutamide, so avoid this concomitant if possible. If required condition, the dose of Obnyx 40mgis reduced to 80mg. Obnyx 40mgtablet combined with CYP3A4 inducers, causes depletion of AUC of Enzalutamide and its active metabolite. CYP3A4 inducers like rifampicin, anti-convulsants, st. Johns wort. This combination should be avoided, in unavoidable condition the dose of Obnyx 40mg is increased up to 240mg. Obnyx 40mg with st. Johns wort causes depletion of Enzalutamide exposure.
Obnyx 40mg with CYP3A4 strong inducer, CYP2C9 & CYP2C19 moderate inducers; CYP3A4 strong inducer: Midazolam CYP2C9: warfarin CYP2C19: Omeprazole The concurrent use of Obnyx 40mg with these drugs may cause depletion of plasma exposure of these drugs. Drugs metabolized by CYP3A4 such as cyclosporine, dihydroergotamine, fentanyl, pimozide, quinidine, sirolimus etc combined with Obnyx 40mg causes decreasing the exposure of these drugs.
Obnyx 40mg is contraindicated to pregnancy conditions, which may causes fetal harm Anaphylactic reactions occurs, if patients are contraindicated to the component occurred in Obnyx 40mg tablets
PREGNANCY & LACTATION
The pregnancy category of Obnyx 40mg tablet is X Obnyx 40mg tablets are contraindicated to pregnancy conditions; it may cause fetal harm even to death. Obnyx 40mg tablets are contraindicated in lactation period, breast feeding should not be recommended.
The storage condition of Obnyx 40mg tablets container at 20°C to 25°C (68°F to 77°F). Container should be kept at dry and cool place.
In case of over dosage of Obnyx 40mg tablets, patients must provided with some supportive measures and discontinue the therapy. The half life of Obnyx 40mg is occurs for 5.8 days. Seizure is the major adverse effect occurred due to over dosage of Obnyx 40mg. Seizure is not described at ≤240mg daily; since three seizures occurs at 360mg, 480mg and 600mg daily.
Obnyx 40mg is a chemo tablets, if patient fail to take the dose of Obnyx 40mg tablets must be consult with medical oncologist and take the dose within a time. In any other way the missed dose should be avoid and follow the regular dosing schedule.