If rifapentine or rifampin are used  in late pregnancy, coagulation should be monitored due to a possible increased risk of maternal postpartum hemorrhage and infant bleeding. Adverse effects
Common side effects include allergic reaction, anemia, neutropenia, elevated transaminases, and pyuria. Overdoses have been associated with hematuria and hyperuricemia. Contraindications
Rifapentine should be avoided in patients with an allergy to the rifamycin class of drugs. This drug class includes rifampicin and rifabutin. Interactions
Rifapentine induces metabolism by CYP3A4, CYP2C8 and CYP2C9 enzymes. It may be necessary to adjust the dosage of drugs metabolized by these enzymes if they are taken with rifapentine. Examples of drugs that may be affected by rifapentine include warfarin, propranolol, digoxin, protease inhibitors and birth control pills. Chemical structure
The chemical structure of rifapentine is similar to that of rifamycin, with the notable substitution of a methyl group for a cyclopentane (C5H9) group. History
Rifapentine was first synthesized in 1965, by the same company that produced rifampicin. The drug was approved by the U.S. Food and Drug Administration (FDA) in June 1998. It is made from rifampicin.Rifapentine was granted orphan drug designation by the FDA in June 1995, and by the European Commission in June 2010. Society and culture
Cancer-causing impurities
In August 2020, the U.S. Food and Drug Administration (FDA) became aware of nitrosamine impurities in certain samples of rifapentine. The FDA and manufacturers are investigating the origin of these impurities in rifapentine, and the agency is developing testing methods for regulators and industry to detect the 1-cyclopentyl-4-nitrosopiperazine (CPNP).
Unlike mesoblastic nephroma, clear cell sarcoma of the kidney presents with metastasis, particularly to bone, in 5-6% of cases; it histology is diverse and has been mistaken for mesoblastic nephroma. One chromosomal translocations t,(10;17)(q22;p13), has been repeatedly reported to be associated with clear cell sarcoma of the kidney. Infantile myofibromatosis is a fibrous tumor of infancy and childhood most commonly presenting during the first 2 years of life as a single subcutaneous nodule of the head and neck region or less commonly as multiple lesions of skin, muscle, bone, and in ~33% of these latter cases, visceral organs. All of these lesions have an excellent prognosis and can regress spontaneously except for those in which there is visceral involvement where the prognosis is poor. While infantile myofibromatosis and classic mesoblastic nephroma have been suggested to be the same diseases because of their very similar histology, studies on the distribution of cell-type markers (i.e. cyclin D1 and Beta-catenin) indicate that they have different cellular origins. Treatment
Based on a survey of >800, surgical removal of the entire involved kidney plus the peri-renal fat appeared curative for the majority of all types of mesoblastic nephroma; the patient overall survival rate was 94%. Of the 4% of non-survivors, half were due to surgical or chemotherapeutic treatments. Another 4% of these patients suffered relapses, primarily in the local area of surgery rare cases of relapse due to lung or bone metastasis.. About 60% of these recurrent cases had a complete remission following further treatment.