Ritonavir, sold under the brand name Norvir, is an antiretroviral medication used along with other medications to treat Acquired Immune Deficiency Syndrome (AIDS), the illness caused by the human immunodeficiency virus (HIV). In addition, it has been learned that if it is used along with other medications, it can treat hepatitis C and Covid-19.
Hepatitis C is a serious viral disease that causes inflammation of the liver and liver damage. It is spread mainly through blood-to-blood contact, blood transfusions, an organ transplant before 1992, using drugs that involve needles or straws, needlestick injuries in healthcare settings, the use of unsterilized tattoo equipment, sharing personal items such as razors or toothbrushes, and sexual contact with a person who has hepatitis C. Covid-19 is a severe acute viral disease that primarily attacks the respiratory system.
How Is Ritonavir Used?
This treatment with a combination of ritonavir and other drugs is known as “highly active antiretroviral therapy” (HAART). Ritonavir is a protease inhibitor used in combination with other protease inhibitors. Ritonavir is rarely used by itself. Rather it serves as a booster for other protease inhibitors. This discovery about how best to use ritonavir has greatly reduced the incidence of adverse effects and improved the efficacy of HAART.
It has been discovered that it can also be used in combination with other medications to treat hepatitis C and COVID-19. It is taken by mouth and has been used as capsules and tablets. The ritonavir tablets are, however, more effective, and taking the drug in tablet form may make it more effective.
Among the more common side effects of ritonavir are nausea, vomiting, loss of appetite, diarrhea, and numbness of the hands and feet. More significant side effects include liver complications, pancreatitis, allergic reactions, and heart arrhythmias. Ritonavir may also interact with several other medications, including amiodarone and simvastatin. It is considered acceptable during pregnancy if the dose is kept low.
Ritonavir was patented in 1989 and started to be used as a treatment in 1996. It is on the World Health Organization’s List of Essential Medicines. Ritonavir capsules were approved as a generic medication in the United States in 2020.
Was Retronovir Ever Withdrawn from the Market?
Ritonavir was introduced in 1996 and was originally sold as a capsule that did not require refrigeration. So, it could be stored at room temperature. The capsule contained a crystal form of Ritonavir called form I.
However, like many crystal-form drugs, crystalline ritonavir exhibited a characteristic called “polymorphism.” Polymorphism is the ability of one molecule to crystallize into more than one crystal type or polymorph. The substance’s ability to dissolve can vary in the different crystalline forms’ different arrangements. This, in turn, negatively affected the substance’s ability to be absorbed into a person’s circulatory system, which limited its effectiveness. This characteristic was observed in both forms of Ritonavir.
In 1998, a more stable form was discovered. However, this more stable crystal form lacked the ability to dissolve in liquids, so its effectiveness was also lowered. Because of this lowered effectiveness, it was temporarily removed from the market.
Because even a trace amount of form II can result in the conversion of the more effective form I into form II, the presence of form II threatened to ruin all of the existing supplies of the oral capsule formulation of ritonavir. Form II was even discovered in production lines, thus stopping ritonavir production.
The Abbott company (now AbbVie) that produced ritonavir withdrew the capsules from the market. Doctors who had prescribed it were encouraged to switch to a more stable form of Norvir medication. The Abbott company reportedly lost over $250 million as a result.
The company’s research and development teams solved the problem by replacing the capsule formulation with a refrigerated gelcap. In 2000, Abbott (now AbbVie) received FDA approval for a tablet formulation of lopinavir/ritonavir. This did not require refrigeration. Ritonavir was reformulated to remain form I and not polymorph and re-introduced to the commercial market in 2010.
Ritonavir is also commonly used to inhibit the enzyme that metabolizes other protease inhibitors. This inhibition enables the use of lower doses of these other medications.
Is Ritonavir Used Now as a Treatment for HIV?
Ritonavir is prescribed with other antiretroviral agents for treating HIV-1 in patients. It was first developed as an independent antiviral treatment, but now it is most commonly used to enhance other antiretroviral drugs. Ritonavir is effective in preventing the replication of the HIV-1 virus. It is a protease inhibitor, which works by blocking HIV-1 protease, an enzyme critical in the reproductive cycle of HIV-1.
It can be used in infants, children, adolescents, and adults to treat HIV infection.
Is Ritonavir a Treatment for COVID-19?
In December 2021, the federal Food and Drug Administration (FDA) gave the combination of nirmatrelvir and ritonavir authorization for emergency use to treat Covid-19. These medications are sold under the brand name “Paxlovid.” Paxlovid is not authorized for use to prevent COVID-19.
In 2021, the Medicines and Healthcare products Regulatory Agency (MHRA) in the United Kingdom approved the same combination of ritonavir as had been approved in America. It is for treating people with mild to moderate COVID-19 who are at high risk of developing a more severe illness.
What Are the Side-Effects of Ritonavir?
When the drug is administered at the higher doses at which it was used initially, the side effects of ritonavir are those as follows:
- Asthenia, malaise;
- Diarrhea;
- Nausea and vomiting;
- Abdominal pain;
- Dizziness;
- Insomnia;
- Kidney failure;
- Sweating;
- Taste abnormality;
- Metabolic effects.
New-onset diabetes mellitus, hyperglycemia, ketoacidosis, exacerbation of preexisting diabetes mellitus, spontaneous bleeding in hemophiliacs, and pancreatitis have been reported.
What Are My Remedies If I Have Been Injured by Ritonavir?
If a person believes that the use of ritonavir has injured them, they have two options for seeking a remedy depending on the facts of their case. One would be to sue the doctor who prescribed the medication to them for medical malpractice.
An example of facts that might justify a lawsuit for medical malpractice would be if the doctor should not have prescribed the medication for a person because they take another medication known to interact negatively with ritonavir. A person would have to prove some facts that show that their doctor committed medical negligence in connection with their treatment of the person with ritonavir.
Another option would be to sue the manufacturer and distributors of ritonavir for strict product liability. In a case for strict product liability, the injured person would not have to prove that anyone connected with the drug or the treatment with the drug was negligent. Rather the person would have to prove that the product, ritonavir, was defective in some way and that the defect caused the person’s injury.
Product defects usually fall into one of three categories, warning defects, manufacturing defects, and design defects. A person would need to show in what way ritonavir is defective and how the defect caused their injury. For example, they might have experienced a negative side-effect not included on the warning label for the drug.
Both lawsuits for medical malpractice and those for strict product liability would obtain an award of compensatory damages for the injured person. This would cover their economic and non-economic losses, such as lost income, the cost of the treatment for their injuries, and pain and suffering.
Do I Need the Help of a Lawyer for My Ritonavir Issue?
If you believe you have been injured by taking ritonavir, consult a class action lawyer. Your lawyer can review the facts of your case and determine whether they would support a case for medical malpractice or strict product liability. Your lawyer would work to protect your rights and, if possible, recover damages to compensate you for your losses.
