One study appeared to show that gw 50156 side effects included the growth of cancer cells but on further inspection, the results could be considered misleading. The study of gw1516 which was carried out on mice included 1000 times the recommended dose, taken over a prolonged period of time. As no individual would be taking such an inflated level of gw501516, there is debatable value attached to this particular study. Nevertheless, despite the criticism of this study, it was sufficient for GSK to drop the project so shouldn’t be dismissed completely.
It was once commonly used during PCT in the belief it will aid testosterone restoration, however this is flawed due to its mechanism of action. The drug mimics the effects of LH in the body, stimulating the Leydig cells to produce testosterone in the testes . This can be fruitful in rectify existing, or avoiding testicular atrophy on cycle. It will not aid the process of recovery in the post cycle phase however, as the drug will bring about heightened oestrogen levels due to the greater aromatising of the testosterone being produced in the testes , thus bringing about greater inhibition of the HPTA .