I would suggest

--------------------------------------------------
Note added at 24 mins (2018-03-19 23:20:07 GMT)
--------------------------------------------------

Platelets, also called thrombocytes are a component of blood whose function is to stop bleeding by clumping and clotting blood vessel injuries. Platelets have no cell nucleus: they are fragments of cytoplasm that are derived from the megakaryocytes of the bone marrow, and then enter the circulation. These unactivated ...
‎Megakaryocyte · ‎Thrombocytosis · ‎Plateletpheresis · ‎CXCL4

--------------------------------------------------
Note added at 25 mins (2018-03-19 23:21:01 GMT)
--------------------------------------------------

https://es.wikipedia.org/wiki/Plaqueta
Las plaquetas liberan un gran número de factores de crecimiento incluyendo el factor de crecimiento derivado de plaquetas (PDGF, por platelet derived growth factor), un potente agente quimiotáctico, y el factor de crecimiento transformante beta, (TGF-beta, por transforming growth factor) el cual estimula el depósito de ...

--------------------------------------------------
Note added at 27 mins (2018-03-19 23:23:19 GMT)
--------------------------------------------------

so your sentence might read: aimed at lowering (the) platelet count

--------------------------------------------------
Note added at 29 mins (2018-03-19 23:25:02 GMT)
--------------------------------------------------

and as an explanatory ref:

https://www.wikihow.com/Decrease-Platelets

Eat raw garlic to decrease the number of platelets in your blood. Raw or crushed garlic contains a compound called "allicin" which affects the body's ability to make platelets, therefore decreasing the number of platelets in the blood. Your body responds to the lower platelet level by improving its immunity, which helps to ...

--------------------------------------------------
Note added at 33 mins (2018-03-19 23:28:56 GMT)
--------------------------------------------------

and here's something on "warfarin": https://en.wikipedia.org/wiki/Warfarin

Warfarin is also used in antiphospholipid syndrome. It has been used occasionally after heart attacks (myocardial infarctions), but is far less effective at preventing new thromboses in coronary arteries. Prevention of clotting in arteries is usually undertaken with antiplatelet drugs, which act by a different mechanism from ...

This was my first thought, before seeing Joseph's link to Emma's answer.

Spanish term (edited): Objetivar

Some more options.
If there was previously a suspicion of a decrease in platelets, and then they were measured and found to be decreased in fact, "upon confirmation of a decrease" might work well in your phrase.