Friday, December 9, 2011

Generic Lipitor Hits the Market - Is it the Same Medicine?

Pfizer’s cholesterol-lowering Lipitor now faces competition from generic versions of the drug for the first time since it’s U.S. patent expired Wednesday. The pharmaceutical company’s blockbuster hit the market in 1997 and generated sales of $10.7 billion last year alone. Rivalry comes from India’s largest drug manufacturer, Ranbaxy Laboratories Ltd. The new generic drug will be labeled “atorvastatin calcium,” which is the chemical name of Lipitor.

Is there a clinical difference between Lipitor and its generics? Director of Consumer Reports Health Ratings Center John Santa says that there will not be a meaningful difference. In order to gain FDA approval, generics must contain the same active ingredients and be as safe and effective.

However, a good number of patients have experienced difficulties when a generic equivalent was introduced. According to the FDA, drug approval is based on three factors:

  1. Pharmaceutical Equivalency – Does the generic contain the same chemically active ingredients and are they identical is dosage form and strength?These criteria may be affected by many things such as: 
    • Variations in inactive ingredients
    • Manufacturing facilities in different parts of the world
    • In oral drugs, capsule content is allowed to vary 7% over or 7% under the stated content, resulting in a possible 14% variation.
    • Age of the patient
  2. Bioavailibility – Based on the amount of drug absorbed and the speed of absorption. Some generics may be absorbed faster or slower than the brand name drug.
  3. Bioequivalence – Are the generic and the brand-name drug functionally equivalent? In order to approve any generic drug, the FDA requires that the generic be effective within a 20% range of the original patented drug. This means that it could be 20% more effective OR 20% less effective than its brand-name counterpart. For prescriptions such as anti-depressants or hormone-based medications, which require precise dosages, this could be the difference as to whether the generic is effective or ineffective for you.
Another risk associated with generic drugs is that a patient could receive a different generic each time they fill their prescription. Also, the difference in inactive ingredients found in generics may react differently with medications you are already taking.

So what should you do if you have the choice between a brand-name and a generic?
  • Talk to your doctor. Ask if the generic counterpart is known to be as effective and if there are side effects. Be sure your doctor know all of your current medications and dosages. 
  • Listen to your own body. Have you noticed any changes after switching to a generic? How do you feel? Are you experiencing any adverse reactions? These can all be red flags as to whether that generic is the best choice for you.
By far, generic drugs are not bad things, and often they save us a lot of money, but they are not always as good as the “original.”

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