Kryxana — Ribociclib 200 mg, 21 Film-Coated Tablets

Kryxana 200 is formulated as film-coated tablets for oral administration. Each tablet contains:

• Active Ingredient: Ribociclib succinate — 254.40 mg (equivalent to 200 mg of free ribociclib).
• Excipients: Microcrystalline cellulose, crospovidone (type A), hypromellose (low viscosity), colloidal anhydrous silica, magnesium stearate.
• Film Coating: Opadry (partially hydrolyzed polyvinyl alcohol, titanium dioxide, soya lecithin, xanthan gum, talc, red iron oxide, black iron oxide).

Pharmacodynamics: Ribociclib is a selective inhibitor of cyclin-dependent kinases CDK4 and CDK6. These enzymes, upon binding to D-cyclins, play a crucial role in signaling pathways leading to cell cycle progression and cellular proliferation. The cyclin D-CDK4/6 complex phosphorylates the retinoblastoma protein (pRb). Inhibition of pRb phosphorylation by ribociclib leads to cell cycle arrest at the G1/S checkpoint, suppressing DNA synthesis and blocking tumor cell proliferation in breast cancer models. In preclinical studies, combining ribociclib with anti-estrogens (such as letrozole) yielded synergistic inhibition of HR+ tumor cell growth.

Pharmacokinetics: Following oral administration, ribociclib is rapidly absorbed from the gastrointestinal tract, achieving peak plasma concentration (Cmax) in 1 to 5 hours (median 2 hours). Food intake has no clinically meaningful effect on the extent of absorption. Plasma protein binding is approximately 70%. Ribociclib undergoes extensive hepatic metabolism mediated primarily by cytochrome P450 enzyme CYP3A4. Elimination occurs mainly via feces (approx. 69%) and kidneys (approx. 24%), predominantly as metabolites. The mean plasma elimination half-life (T1/2) at steady-state ranges from 30 to 55 hours.

Kryxana 200 mg is indicated for the treatment of adult patients with the following oncological conditions:

• 🔹 Advanced or Metastatic Breast Cancer: Treatment of pre/perimenopausal or postmenopausal women, and men, with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced or metastatic breast cancer.
• 🔹 Combination Regimens: Used in combination with an aromatase inhibitor (letrozole, anastrozole) or fulvestrant as initial endocrine-based therapy or following disease progression on endocrine therapy (in pre/perimenopausal women, endocrine therapy should be combined with a LHRH agonist).

Treatment with Kryxana 200 must be initiated and managed by a qualified oncologist. Tablets should be swallowed whole with water and must not be chewed, broken, or crushed. Administer orally once daily at approximately the same time each day, preferably in the morning, with or without food.

• Recommended Starting Dose: 600 mg (three 200 mg tablets) orally once daily for 21 consecutive days followed by 7 days off treatment, completing a 28-day full cycle.
• Concomitant Therapy: Administered alongside letrozole (2.5 mg once daily continuously through the 28-day cycle) or fulvestrant (500 mg intramuscularly on Days 1, 15, 29, and monthly thereafter).
• Dose Modifications for Toxicity: Management of severe neutropenia, hepatotoxicity, or QT interval prolongation may require dose reductions: 1st reduction to 400 mg/day (two 200 mg tablets); 2nd reduction to 200 mg/day (one 200 mg tablet). Discontinue if 200 mg/day is not tolerated.
• Missed Dose: If a dose is missed or vomiting occurs after taking a dose, do not administer an additional dose that day. Resume regular dosing the following day at the scheduled time.

Kryxana 200 is contraindicated in patients with the following conditions:

• ⛔ Hypersensitivity: Known hypersensitivity to ribociclib, peanut, soy, or any of the excipients in the tablet formulation.
• ⛔ Pregnancy and Lactation: Strictly contraindicated. Ribociclib causes fetal harm and embryo-fetal toxicity. Breastfeeding is prohibited during treatment.
• ⛔ Pediatric Population: Safety and effectiveness in pediatric patients under 18 years of age have not been established.
• ⛔ QT Prolongation: Baseline QTcF interval greater than 450 ms, long QT syndrome, or concurrent administration with potent CYP3A4 inhibitors / QT-prolonging drugs.

Ribociclib is extensively metabolized by CYP3A4 and acts as a moderate-to-strong inhibitor of CYP3A4:

• ⚠️ Strong CYP3A4 Inhibitors: Co-administration with ketoconazole, itraconazole, clarithromycin, or grapefruit juice significantly increases ribociclib exposure and toxicity risk. Avoid concomitant use.
• ⚠️ Strong CYP3A4 Inducers: Co-administration with rifampin, phenytoin, carbamazepine, or St. John's Wort decreases ribociclib plasma concentrations and efficacy.
• ⚠️ CYP3A4 Substrates with Narrow Therapeutic Index: Ribociclib may increase concentrations of drugs like midazolam, sirolimus, and tacrolimus.
• ⚠️ QT-Prolonging Drugs: Antiarrhythmics (amiodarone, sotalol) and antibiotics (levofloxacin) combined with ribociclib increase the risk of severe cardiac arrhythmias.

The use of Kryxana 200 during pregnancy and lactation is strictly contraindicated due to severe risks to the fetus:

• Females of Reproductive Potential: Must undergo pregnancy testing prior to treatment initiation. Female patients must use effective contraception during treatment with Kryxana 200 and for at least 21 days after the final dose.
• Male Patients: Male patients with female partners of reproductive potential must use effective contraception during treatment and for at least 21 days after the last dose, as ribociclib may impair male fertility and spermatogenesis.
• Lactation: It is unknown whether ribociclib is excreted in human milk. Breastfeeding must be discontinued during treatment and for 21 days after the final dose.

The most common and clinically significant adverse reactions reported with Kryxana 200 include:

• 🔴 Hematologic Toxicity: Neutropenia (most frequent, occurring in >70% of patients), leukopenia, anemia, lymphopenia, thrombocytopenia, and febrile neutropenia.
• 🟡 Gastrointestinal Tract: Nausea, diarrhea, vomiting, constipation, stomatitis, abdominal pain, and decreased appetite.
• 🟠 Hepatobiliary and Cardiac: Increased serum ALT, AST, and bilirubin levels (hepatotoxicity), and QTcF interval prolongation on ECG.
• 🟢 General and Systemic Reactions: Fatigue, alopecia, rash, pruritus, headache, insomnia, peripheral edema, and dyspnea.

There is no known specific antidote for ribociclib overdose:

• Symptoms: Exceeding the recommended dose may lead to severe myelosuppression (profound neutropenia), severe gastrointestinal toxicities, hepatotoxicity, and dangerous QTcF prolongation with potential ventricular arrhythmias.
• Management: In case of overdose, discontinue Kryxana 200 immediately. Induce gastric decontamination or administer activated charcoal, initiate continuous ECG monitoring, monitor hepatic and hematologic parameters, and provide supportive symptomatic care.

Storage instructions to maintain chemical stability and therapeutic activity:

• 🌡️ Temperature Control: Store in original container in a dry place protected from light at temperatures not exceeding 30 °C.
• 👶 Safety Precautions: Keep out of reach and sight of children and pets.
• ⏳ Expiration Date: Stamped on the outer carton and blister packaging. Do not use after the expiration date (Exp. Date). Unused medication must be disposed of according to hazardous waste guidelines.

Authentic Kryxana 200 mg (21 Film-Coated Tablets) manufactured by Novartis features distinct security and packaging characteristics:

• 🛡️ Top Red-White-Yellow Banner: The top border of the outer carton features a signature geometric design with diagonal white, orange, and yellow stripes set against a solid red background.
• 🔒 Brand Name and Novartis Logo: The brand name «KRYXANA» is printed in prominent bold red font alongside the classic Novartis four-diamond geometric logo in red and yellow. An adjacent red block clearly highlights «200 mg».
• 🔍 Regional Sale Restriction Notice: The bottom left panel displays the explicit statement printed in black font: «FOR SALE IN INDIA ONLY».
• 🔢 2D DataMatrix Barcode: The front box features a 2D DataMatrix code encoding the GTIN, Batch Number (10), Expiry Date (17), and unique Serial Number (21). Hindi language text «क्रिक्साना २०० मिग्रा» is printed directly under the main title. Package size «21 film-coated tablets» is clearly stated at the bottom right. Tamper-evident seals are present on box end flaps.