Nestoron (Elcometrine) is a 19-norprogesterone derivative with high affinity and selectivity for progesterone receptors. Nestoron is a highly selective and potent progestogen that can be used as a hormonal contraceptive[1][2].
Nestoron (400 μCi 3H Nestoron/kg BW; subcutaneous injection; female Sprague-Dawley rats) treatment results in the Cmax in the blood and plasma are 58.1 and 95.5 ng equiv. 3H Nestoron/g, with t1/2 of 15.6 hours. Approximately, 81.4% and 7.62% of the administered dose is excreted via feces and urine, respectively[1].
References:
[1]. Prasad PV, et al. Single-dose pharmacokinetics of Nestorone, a potential female-contraceptive.Steroids. 2010 Mar;75(3):252-64. Epub 2010 Jan 11.
[2]. Hussain R, et al. Progesterone and Nestorone facilitate axon remyelination: a role for progesterone receptors. Endocrinology. 2011 Oct;152(10):3820-31.