4 ms·

Doesn't that mean they're not chemically equivalent?

mikeyouse 7y ago
The active ingredient is the same - the binders and fillers and capsule materials are mostly inert. This isn't true for all drugs - for the blood thinner Coumadin, you're meant to stick to generic or brand name and not switch between the two since there are known differences in efficacy.
- MegaButts 7y ago
  I understand that. OP said: > There is no sensible reason to pay a premium for brand name if the generic is chemically equivalent. If they're not chemically equivalent and have different medicinal effects as a result, then it's much easier to justify a price difference. I understand chemistry is more than just a list of ingredients. It's how those ingredients are combined that gives them their unique interactions.
  - JMTQp8lwXL 7y ago
    For sake of the discussion here, bio-equivalence is the more helpful way for meaningfully comparing generic to brand names. The filler might be different, but if the biological effect is identical at half the cost, one would be prudent to chose the generic option.
    - perl4ever 7y ago
      Yet we see drugs that are, say, 100 times the cost of the generic. So how can that happen; how is that sustainable? Presumably nearly everyone starts on the generic, and then switches to the brand name if they have problems with the generic. So there is actually not competition so much as price discrimination! You can't tell someone who the generic has failed that they are equivalent, because their only hope is that they are not! Not only is the generic no longer an alternative, but psychologically, it's easier to put your hope in a super-expensive option because of the cliche "you get what you pay for". So I think telling people continually that generics are identical is not helpful, because it's not information. It's an assumption, which might be true or it might not be, but is essentially never helpful to any individual in making a decision.
- jsight 7y ago
  I do not think the results for Coumadin/Warfarin are at all clear: https://www.ncbi.nlm.nih.gov/pubmed/21449627 https://www.ncbi.nlm.nih.gov/pubmed/21449627
  - mikeyouse 7y ago
    Thanks for the update - interesting study.
thereisnospork 7y ago
Chemically equivalent but formulated differently. Think hot dog vs. corn dog: the meat is the same but the packaging is slightly different. The packaging can have a surprisingly large effect on drug absorption, and therefore efficacy. Notably with difficult to dissolve drugs a lot of work typically goes into formulating them to be more efficiently processed by the intestinal tract.
- refurb 7y ago
  The FDA approves generics based on bioequivalence, not just chemical composition. In order to be an "AB" rated generic (and used as a substitute for the branded product), the generic has to fall between 80-125% bioequivalence of the brand, which measure dissolution and absorption. The fillers in the generic don't have to be the same as the branded product, but the drug does have to behave the same as the branded product.
  - perl4ever 7y ago
    There was an issue I read about with a drug where they did not test all the different dosages of a generic, and I think the behavior of one of the doses was not as expected because it didn't dissolve well or something. This was a psychiatric drug, and so of course, reports of problems went unheeded for years because patients were assumed to be imagining things. Saying "the drug does have to behave the same as the branded product" is like saying "the product as delivered does have to match the spec".
    - refurb 7y ago
      Yup. There have been a handful of approved generics that didn’t have bioequivalence to the branded. It’s not a perfect process, but it works in nearly all the cases.
      - perl4ever 7y ago
        We don't know that "it works in nearly all the cases". We know that in nearly all the cases, any issues don't rise to the level where the FDA or the public identifies them. I doubt that the system is constructed in such a way that nearly all the problems are identified. It seems to me that because drugs are developed to meet the absolute minimum standards for proving efficacy and safety, there's inherently going to be little if any margin for error in the manufacturing process and hardly any way to analyze problems. When reporting potential side effects, most drugs are going to be just above the noise level in their principle effect, so how are you going to determine what is a random unrelated issue and what is a negative side effect, and what is the consequence of a QA or design failure?
Rychard 7y ago
My understanding is that only the "active ingredient" is the same. Everything else is subject to cost-cutting, as there are many fillers and binders to choose from, and they're priced differently.

The active ingredient is the same - the binders and fillers and capsule materials are mostly inert. This isn't true for all drugs - for the blood thinner Coumadin, you're meant to stick to generic or brand name and not switch between the two since there are known differences in efficacy.

MegaButts 7y ago
I understand that. OP said: > There is no sensible reason to pay a premium for brand name if the generic is chemically equivalent. If they're not chemically equivalent and have different medicinal effects as a result, then it's much easier to justify a price difference. I understand chemistry is more than just a list of ingredients. It's how those ingredients are combined that gives them their unique interactions.
- JMTQp8lwXL 7y ago
  For sake of the discussion here, bio-equivalence is the more helpful way for meaningfully comparing generic to brand names. The filler might be different, but if the biological effect is identical at half the cost, one would be prudent to chose the generic option.
  - perl4ever 7y ago
    Yet we see drugs that are, say, 100 times the cost of the generic. So how can that happen; how is that sustainable? Presumably nearly everyone starts on the generic, and then switches to the brand name if they have problems with the generic. So there is actually not competition so much as price discrimination! You can't tell someone who the generic has failed that they are equivalent, because their only hope is that they are not! Not only is the generic no longer an alternative, but psychologically, it's easier to put your hope in a super-expensive option because of the cliche "you get what you pay for". So I think telling people continually that generics are identical is not helpful, because it's not information. It's an assumption, which might be true or it might not be, but is essentially never helpful to any individual in making a decision.
jsight 7y ago
I do not think the results for Coumadin/Warfarin are at all clear: https://www.ncbi.nlm.nih.gov/pubmed/21449627 https://www.ncbi.nlm.nih.gov/pubmed/21449627
- mikeyouse 7y ago
  Thanks for the update - interesting study.

thereisnospork 7y ago

Chemically equivalent but formulated differently. Think hot dog vs. corn dog: the meat is the same but the packaging is slightly different. The packaging can have a surprisingly large effect on drug absorption, and therefore efficacy. Notably with difficult to dissolve drugs a lot of work typically goes into formulating them to be more efficiently processed by the intestinal tract.

refurb 7y ago
The FDA approves generics based on bioequivalence, not just chemical composition. In order to be an "AB" rated generic (and used as a substitute for the branded product), the generic has to fall between 80-125% bioequivalence of the brand, which measure dissolution and absorption. The fillers in the generic don't have to be the same as the branded product, but the drug does have to behave the same as the branded product.
- perl4ever 7y ago
  There was an issue I read about with a drug where they did not test all the different dosages of a generic, and I think the behavior of one of the doses was not as expected because it didn't dissolve well or something. This was a psychiatric drug, and so of course, reports of problems went unheeded for years because patients were assumed to be imagining things. Saying "the drug does have to behave the same as the branded product" is like saying "the product as delivered does have to match the spec".
  - refurb 7y ago
    Yup. There have been a handful of approved generics that didn’t have bioequivalence to the branded. It’s not a perfect process, but it works in nearly all the cases.
    - perl4ever 7y ago
      We don't know that "it works in nearly all the cases". We know that in nearly all the cases, any issues don't rise to the level where the FDA or the public identifies them. I doubt that the system is constructed in such a way that nearly all the problems are identified. It seems to me that because drugs are developed to meet the absolute minimum standards for proving efficacy and safety, there's inherently going to be little if any margin for error in the manufacturing process and hardly any way to analyze problems. When reporting potential side effects, most drugs are going to be just above the noise level in their principle effect, so how are you going to determine what is a random unrelated issue and what is a negative side effect, and what is the consequence of a QA or design failure?

Rychard 7y ago

My understanding is that only the "active ingredient" is the same. Everything else is subject to cost-cutting, as there are many fillers and binders to choose from, and they're priced differently.