Population Council Research that makes a difference

Narender Kumar, Ph.D.

Senior Scientist

Dual Health Benefits: Nestorone
Council scientists at the Center for Biomedical Research are developing safer and more effective long-acting contraceptives that have dual health benefits, using molecules with selective binding to hormone receptors, such as Nestorone®, a derivative of progesterone.
(1/2010 - ongoing)
Topics: New and improved reproductive technologies; Reproductive health biomedical research; Technologies for women
Countries: France, United States

MENT® (more)
Council researchers are working to develop methods of contraception for men that contain MENT®, a synthetic steroid that resembles testosterone
(1/2005 - ongoing)
Topics: Technologies for men
Countries: Chile, Dominican Republic, Germany, United Kingdom, United States

Nestorone® (more)
Many of the products under development at the Council employ Nestorone, a versatile synthetic progestin similar to the natural hormone progesterone
(1/2005 - ongoing)
Topics: New and improved reproductive technologies; Technologies for women
Countries: United States

Subdermal Implants for Men (more)
Studies have found that men are interested in taking more responsibility for family planning; an implant for men is the Council's lead product in male contraception.
(1/2005 - ongoing)
Topics: Technologies for men
Countries: Chile, Dominican Republic, Germany, United Kingdom, United States

Transdermal Delivery Systems for Men (more)
Council research has demonstrated that MENT permeates the skin significantly better than two other androgens and is safe for further development as a hormone therapy method for men.
(1/2005 - ongoing)
Topics: Technologies for men
Countries: Chile, United States

One-year Combination Vaginal Ring, Phase 3 Study (more)
The NES/EE vaginal ring is a user-controlled method that can be reused for one year.
(9/2005 - 6/2009)
Topics: Technologies for women
Countries: Americas, Australia, Europe, United States

One-year Combination Vaginal Ring, Phase 2 Study (more)
The NES/EE vaginal ring is a user-controlled method that can be reused for one year.
(9/2005 - 11/2008)
Topics: Technologies for women
Countries: Chile, Dominican Republic, Sweden, United States

Narender Kumar, Ph.D.

Senior Scientist

7a-methyl-19-nortestosterone (MENT®): The Population Council's contribution to research on male contraception and treatment of hypogonadism  (abstract) 
Nieschlag,Eberhard; Kumar,Narender; Sitruk-Ware,Regine
Contraception Published online ahead of print, 12 October
Publication date: 2012

A new combination of testosterone and nestorone transdermal gels for male hormonal contraception  (abstract) 
Ilani,Niloufar; Roth,Mara Y.; Amory,John K.; Swerdloff,Ronald S.; Dart,Clint; Page,Stephanie T.; Bremner,William J.; Sitruk-Ware,Regine; Kumar,Narender; Blithe,Diana; Wang,Christina
Journal of Clinical Endocrinology and Metabolism 97(10): 3476-3486
Publication date: 2012

Effects of a novel estrogen-free, progesterone receptor modulator-contraceptive vaginal ring on inhibition of ovulation, bleeding patterns and endometrium in normal women  (abstract) 
Brache,Vivian; Sitruk-Ware,Regine; Williams,A.; Blithe,Diana; Croxatto,Horacio B.; Kumar,Narender; Kumar,Sushma; Tsong,Yun-yen; Sivin,Irving; Nath,Anita; Sussman,Heather; Cochon,Leila; Miranda,Maria Jose; Reyes,Veronica; Faundes,Anibal; Mishell,Daniel R.,Jr.
Contraception 85(5): 480-488
Publication date: 2012

7α-methyl-19-nortestosterone vs. testosterone implants for hypogonadal osteoporosis: A preclinical study in the aged male orchidectomized rat model  (abstract) 
Sinnasael,M.; Callewaert,F.; Morreels,M.; Kumar,Narender; Sitruk-Ware,Regine; Van Proeyen,K.; Hespel,P.; Boonen,Steven; Claessens,F.; Vanderschueren,Dirk
International Journal of Andrology 34(6 pt 2): 601-611
Publication date: 2011

Progesterone and nestorone facilitate axon remyelination: A role for progesterone receptors  (abstract) (PDF) 
Hussain,Rashad; El-Etr,Martine; Gaci,O.; Rakotomamonjy,J.; Macklin,W.B.; Kumar,Narender; Sitruk-Ware,Regine; Schumacher,Michael; Ghoumari,Abdel M.
Endocrinology 152(10): 3820-3831
Publication date: 2011

7α-hydroxytestosterone affects 11ß-hydroxysteroid dehydrogenase 1 direction in rat Leydig cells  (abstract) 
Hu,Guo-Xin; Lian,Qing-Quan; Chen,Bing-Bing; Vishwanath Prasad,Pramod; Kumar,Narender; Zheng,Zhi-Qiang; Ge,Renshan
Endocrinology 151(2): 748-754
Publication date: 2010

Single-dose Pharmacokinetics of Nestorone, a potential female-contraceptive  (abstract) 
Vishwanath Prasad,Pramod; Bashir,Mohammad; Sitruk-Ware,Regine; Kumar,Narender
Steroids 75(3): 252-264
Publication date: 2010

Central modifications of allopregnanolone and ß-endorphin following subcutaneous administration of Nestorone  (abstract) 
Lenzi,E.; Pluchino,N.; Begliuomini,S.; Casarosa,E.; Merlini,S.; Giannini,A.; Luisi,M.; Kumar,Narender; Sitruk-Ware,Regine; Genazzani,Andrea R.
Journal of Steroid Biochemistry and Molecular Biology 116(1-2): 15-20
Publication date: 2009

Combined transdermal testosterone gel and the progestin Nestorone suppresses serum gonadotropins in men  (abstract) (PDF) 
Mahabadi,Vahid; Amory,John K.; Swerdloff,Ronald S.; Bremner,William J.; Page,Stephanie T.; Sitruk-Ware,Regine; Christensen,Peter D.; Kumar,Narender; Tsong,Yun-yen; Blithe,Diana; Wang,Christina
Journal of Clinical Endocrinology and Metabolism 94(7): 2313-2320
Publication date: 2009

Distribution, metabolism and excretion of a synthetic androgen 7α-methyl-19-nortestosterone, a potential male-contraceptive  (abstract) 
Vishwanath Prasad,Pramod; Arumugam,Ramamani; Willman,Mark; Ge,Renshan; Sitruk-Ware,Regine; Kumar,Narender
Steroids 74(1): 121-131
Publication date: 2009

Effect of sexual intercourse on the absorption of levonorgestrel after vaginal administration of 0.75 mg in Carraguard® gel: A randomized, cross-over, pharmacokinetic study  (abstract) 
Brache,Vivian; Croxatto,Horacio B.; Kumar,Narender; Sitruk-Ware,Regine; Cochon,Leila; Schiappacasse,Veronica; Sivin,Irving; Munoz,Carla; Maguire,Robin A.; Faundes,Anibal
Contraception 79(2): 150-154
Publication date: 2009

An initial pharmacokinetic study with a Metered Dose Transdermal System® for delivery of the progestogen Nestorone® as a possible future contraceptive  (abstract) 
Fraser,Ian S.; Weisberg,Edith; Kumar,Narender; Kumar,Sushma; Humberstone,Andrew J.; McCrossin,Louise; Shaw,Deborah; Tsong,Yun-yen; Sitruk-Ware,Regine
Contraception 76(6): 432-438
Publication date: 2007

Effect of a single vaginal administration of levonorgestrel in Carraguard® gel on the ovulatory process: A potential candidate for 'dual protection' emergency contraception  (abstract) 
Brache,Vivian; Croxatto,Horacio B.; Sitruk-Ware,Regine; Maguire,Robin A.; Montero,Juan Carlos; Kumar,Narender; Salvatierra,Ana Maria; Tejada,Ana-Sofia; Cochon,Leila; Forcelledo,Maria Luisa; Lahteenmaki,Pekka; Alvarez,Francisco; Faundes,Anibal
Contraception 76(2): 111-116
Publication date: 2007

Pharmacokinetic study to compare the absorption and tolerability of two doses of levonorgestrel following single vaginal administration of levonorgestrel in Carraguard® gel: A new formulation for 'dual protection' contraception  (abstract) 
Sitruk-Ware,Regine; Brache,Vivian; Maguire,Robin A.; Croxatto,Horacio B.; Kumar,Narender; Kumar,Sushma; Montero,Juan Carlos; Salvatierra,Ana Maria; Phillips,David M.; Faundes,Anibal
Contraception 75(6): 454-460
Publication date: 2007

Progestins and the brain, affects on sexuality and quality of life 
Sitruk-Ware,Regine; Kumar,Narender
Proceedings of the 6th International Menopause Society (IMS) Workshop, Pisa, Italy
Publication date: 2006

Bone and muscle protective potential of the prostate-sparing synthetic androgen 7α-methyl-19-nortestosterone: Evidence from the aged orchidectomized male rat model  (abstract) 
Venken,Katrien; Boonen,Steven; Van Herck,Erik; Vandenput,Liesbeth; Kumar,Narender; Sitruk-Ware,Regine; Sundaram,Kalyan; Bouillon,Roger; Vanderschueren,Dirk
Bone 36(4): 663-670
Publication date: 2005

Two-year performance of a Nestorone-releasing contraceptive implant: A three-center study of 300 women  (abstract) 
Sivin,Irving; Croxatto,Horacio B.; Bahamondes,Luis; Brache,Vivian; Alvarez-Sanchez,Francisco; Massai,Rebeca; Schechter,Janet; Ranta,Sirpa; Kumar,Narender; Wu,Esther; Tejada,Ana-Sofia; Reyes,Veronica; Travers,Elaine; Allen,Arthur; Moo-Young,Alfred J.
Contraception 69(2): 137-144
Publication date: 2004

A clinical trial of 7α-methyl-19-nortestosterone implants for possible use as a long-acting contraceptive for men  (abstract) 
von Eckardstein,Sigrid; Noe,Gabriela; Brache,Vivian; Nieschlag,Eberhard; Croxatto,Horacio B.; Alvarez-Sanchez,Francisco; Moo-Young,Alfred J.; Sivin,Irving; Kumar,Narender; Small,Margaret; Sundaram,Kalyan; Population Council International Committee for Contraception Research
Journal of Clinical Endocrinology and Metabolism 88(11): 5232-5239
Publication date: 2003

Evidence for tissue selectivity of the synthetic androgen 7α-methyl-19-nortestosterone in hypogonadal men  (abstract) (PDF) 
Anderson,Richard A.; Wallace,A.Michael; Sattar,Naveed; Kumar,Narender; Sundaram,Kalyan
Journal of Clinical Endocrinology and Metabolism 88(6): 2784-2793
Publication date: 2003

Nestorone®: Clinical applications for contraception and HRT  (abstract) 
Sitruk-Ware,Regine; Small,Margaret; Kumar,Narender; Tsong,Yun-yen; Sundaram,Kalyan; Jackanicz,Theodore M.
Steroids 68(10-13): 907-913
Publication date: 2003

Effect of chronic administration of 7α-methyl-19-nortestosterone on serum testosterone, number of spermatozoa and fertility in adult male bonnet monkeys (Macaca radiata)  (abstract) 
Ramachandra,S.G.; Ramesh,V.; Krishnamurthy,H.N.; Kumar,Narender; Sundaram,Kalyan; Hardy,Matthew P.; Rao,A.Jagannadha
Reproduction 124(2): 301-309
Publication date: 2002

Pharmacokinetic study of different dosing regimens of levonorgestrel for emergency contraception in healthy women  (abstract) 
Johansson,Elof D.B.; Brache,Vivian; Alvarez-Sanchez,Francisco; Faundes,Anibal; Cochon,Leila; Ranta,Sirpa; Lovern,Mark; Kumar,Narender
Human Reproduction 17(6): 1472-1476
Publication date: 2002

Chronic toxicity and reversibility of antifertility effect of immunization against gonadotropin-releasing hormone in male rats and rabbits  (abstract) 
Kumar,Narender; Savage,Toyin; DeJesus,William; Tsong,Yun-yen; Didolkar,Ashok K.; Sundaram,Kalyan
Toxicological Sciences 53(1): 92-99
Publication date: 2000

Nestorone®: A progestin with a unique pharmacological profile  (abstract) 
Kumar,Narender; Koide,Samuel S.; Tsong,Yun-yen; Sundaram,Kalyan
Steroids 65(10-11): 629-636
Publication date: 2000

7α-methyl-19-nortestosterone, a synthetic androgen with high potency: Structure-activity comparisons with other androgens  (abstract) 
Kumar,Narender; Crozat,Anne; Li,F.; Catterall,James F.; Bardin,C.Wayne; Sundaram,Kalyan
Journal of Steroid Biochemistry and Molecular Biology 71(5-6): 213-222
Publication date: 1999

Functional role of the c-Abl tyrosine kinase in meiosis I  (abstract) 
Kharbanda,Surender; Pandey,Pramrod; Morris,Patricia L.; Whang,Y.; Zhu,Li-Ji; Kumar,Narender; Yuan,Zhi-Min; Weichselbaum,Ralph; Sawyers,Charles L.; Pandita,T.; Kufe,Donald
Oncogene 16(14): 1773-1778
Publication date: 1998