Skip to 0 minutes and 14 seconds Now, let’s move on to the next therapeutic class, which is an anticoagulant. The first one is Refludan. It is a recombinant hirudin derived from yeast cells. And hirudin is a naturally occurring peptide in the salivary gland of leeches. And I remember a story told by my biochemistry professor when I was in college. It was about farmers working on the rice field in the countryside of Taiwan. And when they were bitten by a parasite, it is the leech. The bleeding would not stop because the saliva of that parasite contains hirudin. And the hirudin is made by recombinant DNA technology into Refludan. And it has indicated for HIT that is the heparin induced thrombocytopenia.
Skip to 1 minute and 31 seconds The second product, Xigris, is a recombinant human activated protein C. It’s indicated for severe sepsis but it was withdrawn in 2011. Not because of any serious reason, but simply because of other newer and the more products coming on the market.
Skip to 2 minutes and 0 seconds Tissue plasminogen activator or the TPA is another class that I want to talk about. TPA is also naturally occurring in our body system but in a very small quantity, that it does not have pharmacological effect. The way it works is that it converts plasminogen into plasmin which lyses fibrin, and I’m pretty sure you are very familiar with this because you must have taken exams and that this is one of the exam questions. It’s indicated for patient with heart attack or having a heart attack or stroke. And it’s to be taken within hours to be effective. Now these are the TPA products, alteplase, reteplase, tenecteplase, and that the third one has longer elimination half-life.
Skip to 3 minutes and 13 seconds And therefore it can be given less frequently. And they are all used in the management of acute MI, myocardial infarction and acute ischemic attack or pulmonary embolism. However, it’s not it for patient predisposed for bleeding, because it was simply worsen the bleeding situation. And again these are the packages. And remember packages will always change. So pay attention to the unit, the numbers printed on the package.
Antocoagulants work via different mechanisms, thrombolytic, antiplatelet or plasminogen activator r-hirudin and drotrecogin are both direct thrombin inhibitors. Tissue plasminogen activator (tPA) is involved in the breakdown of blood clots. All products are produced by recombinant technology nowadays.
Two historical anticoagulants are introduced: r-hirudin, derived from yeast cells and indicated for heparin induced thrombocytopenia (HIT). Drotrecogin, a r-activated protein C indicated for sepsis (withdrawn 2011) Three TPAs used today are Alteplase, Reteplase, and Tenecteplase, of which Tenecteplase is a prolonged release formulation. All of them are indicated for rescue from myocardial infarction or ischemic attack.