What is Jinarc and Tolvaptan used for?
Jinarc is a medicine used in adults with an autosomal dominant polycystic kidney. It is an inherited disorder characterized by the growth of numerous fluid-filled cysts in the kidneys, which end up compromising kidney function and can cause kidney failure. Jinarc is intended for use in patients with normal or moderately reduced kidney function at the start of treatment with Jinarc and rapidly progressing disease. Jinarc contains the active substance tolvaptan.
How do you use Jinarc-Tolvaptan?
Jinarc can only be obtained with a prescription and treatment should be started and monitored under the supervision of doctors experienced in the management of the autosomal dominant polycystic kidney disease and aware of the risks of therapy with Jinarc. Jinarc is available as tablets (15, 30, 45, 60 and 90 mg) and should be given twice a day in two different doses. The initial dose should be 45 mg in the morning and 15 mg in the evening (45 + 15 mg), to be subsequently increased to 60 + 30 mg or 90 + 30 mg, depending on tolerability. The morning dose should be taken at least 30 minutes before breakfast, while the evening dose can be taken with or without food. Doses may need to be reduced in patients treated with other medicines. Patients must take plenty of water during treatment.
For more information, see the package leaflet.
How does Jinarc-Tolvaptan work?
The active substance in Jinarc, tolvaptan, is an antagonist of the V2 receptor of vasopressin: it works by blocking the renal receptors to which the hormone vasopressin binds. Vasopressin regulates the level of water and sodium in the body. In the autosomal dominant polycystic kidney, it is believed that kidney cells do not respond normally to vasopressin, causing the formation of fluid-filled cysts. By blocking vasopressin receptors in the kidneys, Jinarc can slow the formation of cysts.
What benefit has Jinarc-Tolvaptan shown during the studies?
In a main study conducted on 1 445 adults with autosomal dominant polycystic kidney disease in rapid progression, but with normal or moderately reduced kidney function, the efficacy of Jinarc in slowing cyst formation was demonstrated. In the study, Jinarc was compared with placebo (a dummy treatment) and the main measure of effectiveness was the change in kidney size after three years of treatment (a way of measuring the enlargement caused by cyst formation). In patients treated with placebo the overall size of the kidneys increased by 18.8% while in those treated with Jinarc the increase was 9.6%. The effects of treatment were greater during the first year.
What is the risk associated with Jinarc -Tolvaptan?
The most common side effects of Jinarc (which may affect more than 2 in 10 people) are thirst, polyuria (increased urine production), nocturia (need to urinate at night) and pollakiuria (increased need to urinate during the day) . Jinarc has been associated with an increase in certain liver enzymes in the blood (a sign of possible liver problems). For the full list of all side effects reported with Jinarc, see the package leaflet. Jinarc should not be used in patients with increased liver enzymes in the blood or with signs or symptoms of liver damage. Blood tests must be performed to check the patient's liver function before starting treatment with Jinarc and repeat them every month for 18 months and then every three months thereafter. Patients are also advised to monitor symptoms of liver damage (such as loss of appetite, nausea and vomiting, itching, fatigue and pain in the upper right abdominal area) during treatment. Jinarc should not be used in patients with hypovolaemia (reduced fluid in the body) and in patients unable to perceive or respond to thirst. It must not be used in patients with hypernatremia (increased sodium levels in the blood) and in pregnant and lactating women. For the full list of limitations, see the package leaflet.
Why was Jinarc-Tolvaptan approved?
The Agency's Committee for Medicinal Products for Human Use (CHMP) decided that Jinarc's benefits are greater than its risks and recommended that it be approved for use in the EU. The CHMP noted the unmet need for treatments for the autosomal dominant polycystic kidney and considered that Jinarc is effective in slowing down cyst formation and possibly deterioration of renal function in patients with the disease, although further long-term data are expected. Regarding safety, while the most common side effects are manageable, the committee identified hepatotoxicity as the most important risk associated with the use of Jinarc, which was addressed by implementing various measures to minimize the risks (see below).
What measures are being taken to ensure the safe and effective use of Jinarc-Tolvaptan?
A risk management plan has been developed to ensure that Jinarc is used as safely as possible. Based on this plan, safety information has been included in the summary of product characteristics and the package leaflet for Jinarc, including the appropriate precautions to be followed by healthcare professionals and patients. In addition, the company that markets Jinarc will provide patients and doctors who will use the medicine with information on the risk of hepatotoxicity and on the importance of avoiding pregnancies during treatment. The company will also carry out a study to further verify the safety of the medicine, including the risk of hepatotoxicity, a long-term efficacy study of the medicine and an efficacy study in patients with severely reduced kidney function. Further information is available in the summary of the risk management plan.
More information on Jinarc-Tolvaptan
On May 27, 2015, the European Commission issued a marketing authorization for Jinarc, valid throughout the European Union. For more information about treatment with Jinarc, read the package leaflet (also part of the EPAR) or contact your doctor or pharmacist. Last update of this summary: 05-2015.
