The FDA has refused to recall two TB drugs suspected of containing carcinogens because of market demand concerns.

The FDA said it had found high levels of carcinogens in the TB drugs Lyphon and Lyphide, but that it would not require two TB drugs to be removed from the U.S. market for the time being because of concerns that the recall could lead to a shortage of supplies.
Wednesday, the FDA said in a statement that it had found the carcinogen nitrosamine impurities in Lyphopin and Lyphosin drugs.
but the FDA says TB patients can continue to take the drug and can communicate with their doctor if they have any concerns during the course of taking it.
, the FDA is investigating the source of carcinogens in two TB drugs.
is a deadly infectious disease, with about 9,000 cases reported in the United States in 2018, according to the U.S. Centers for Disease Control and Prevention.
found impurities in the drug, a group of drugmakers immediately took the initiative to recall the action.
mylan said it recalled more than 19,000 bottles of Lifton in October because of "elevated levels of unknown impurities," according to the FDA's website.
did not respond to the FDA's decision not to recall.
, which is sold under the Priftin brand in the U.S., has not yet been approved or sold, FDA spokeswoman Jeremy Kahn said in an email.
from this point of view, once the drug is recalled, market supply problems will immediately appear, patients will face the situation of no drug available.
news about the detection of carcinogens in listed drugs has been common in recent years: in 2018, the raw materials of psython were found to contain carcinogens, and more than 20 countries and regions around the world have recalled a variety of sartan drugs on the market.
April, the FDA called for the immediate withdrawal of prescription and over-the-counter drugs containing retinitine from the market, recommending that patients switch to other similar products, such as pyrethroids, simitedins, and esomeprazole.
, the FDA announced that carcinogen levels had been found in some metformin-lowering drugs.
... The discovery of impurities in this drug is similar to previous events, but the specific carcinogens detected in the two TB drugs are different.
's previous recall of drugs, including the high blood pressure drug pyrethroids and chlorosatan, the stomach drug Zantac, and the diabetes drug metformin, contains a carcinogen, mainly a nitrosamine impurity called N-nitrodiamine (NDMA), a known carcinogen found in water and food, including meat, dairy products and vegetables.
impurities found in Lifuping and Licfortin are mainly 1-methyl-4-nitrobenes (MNP) and 1-cyclo-4-nitrobenes (CPNP).
source: 1.FDA balks at recalls for 2 tuberculosis meds despite possible carcinogen 2.Cancer-Cancer-Causing Chemicals Found in Critical Tuberculosis Drugs.