Feb 3 2010
Repros Therapeutics Inc. (NasdaqCM:RPRX) today announced that the
Company has received verbal confirmation from the Division of Metabolic
and Endocrine Drug Products of the Food and Drug Agency that the Company
may initiate its Investigational New Drug Application for the study of
oral Androxal® in the treatment of hypogonadal men with Type
II Diabetes (T2D) with a Phase IIa trial. The FDA noted no clinical hold
issues but added that it may have some comments on the specifics of the
Phase II design. Doses to be tested in the Phase IIa study have been
safely tested for longer durations in trials in men for the treatment of
secondary hypogonadism.
“A Randomized, Parallel,
Double-Blind, Placebo Controlled and Open-Label-Active-Controlled
Exploratory Study to Evaluate the Efficacy of Androxal in Improving
Glycemic Control in Men with Secondary Hypogonadism or Adult-Onset
Idiopathic Hypogonadotrophic Hypogonadism (AIHH) and Type II Diabetes
Mellitus”
The opening Phase IIa study is entitled, “A Randomized, Parallel,
Double-Blind, Placebo Controlled and Open-Label-Active-Controlled
Exploratory Study to Evaluate the Efficacy of Androxal in Improving
Glycemic Control in Men with Secondary Hypogonadism or Adult-Onset
Idiopathic Hypogonadotrophic Hypogonadism (AIHH) and Type II Diabetes
Mellitus”. Repros plans to enroll a total of 60 men into three balanced
parallel arms at several clinical sites comparing placebo to two active
doses. The lead investigator for the study is Glenn R. Cunningham MD,
Professor, Baylor College of Medicine, Division of Diabetes,
Endocrinology & Metabolism, Departments of Medicine & Cellular Biology
and the Medical Director, St. Luke’s Episcopal Hospital – Baylor
Diabetes Program. Dr. Cunningham consulted with Repros in the
development of the protocol.
To be included in the study men, age 20 to 80, must have been previously
diagnosed with T2D mellitus as defined by the American Diabetes
Association criteria for at least 6 months. The men must also have been
receiving a stable dose of an oral hypoglycemic agent (OHA). The men
must have a fasting serum glucose level of greater than 126 mg/dL but
less than or equal to 220 mg/dL and HemoglobinA1c (HbA1c)
between 7% and 9.5% while being treated with their prescribed OHA. The
men must also exhibit a morning testosterone level of less than 300
ng/dL and a serum LH of between 1 and 8 mIU/ml.
Men will be treated for three months. The primary endpoints are the
change in HbA1c from baseline to 3 months as well as the
difference between placebo and the two active arms, the change in
fasting blood glucose from baseline to months 1, 2, and 3 for each
treatment group and the change in total testosterone from baseline to
month 3.
In a 200 patient study of Androxal in hypogonadal men it was noted that
fasting glucose levels were reduced in a significant manner in men whose
glucose levels were greater than 104 mg/dL. It was further noted that
the higher the glucose level the greater the reduction. This effect was
noted in the group of men administered Androxal but not at the same rate
in the placebo or topical testosterone treatment groups. Roughly 20% of
the men in the 200 patient trial were previously diagnosed with diabetes
and were receiving OHAs.
An additional review of the efficacy data that showed these hypoglycemic
effects in men were sustained in those men with blood glucose in the
range typical of T2D that is men whose fasting plasma glucose values
were >126 mg/dL at screening or baseline. In this re-analyzed group
responders were defined as those men who experienced a lowering of their
fasting glucose from baseline by at least 10mg/dL in the three to six
month treatment window. Of the forty-five men whose data were available
six were assessed once over the three month range but most were assessed
three times. In the latter cases responders were those who demonstrated
at least two decreases in fasting plasma glucose out of three
assessments. The placebo group showed 3 responder and 10 non-responders;
the AndroGel group showed 4 responders and 7 non-responders and the two
Androxal groups combined had 16 responders and 5 non-responders. Even
though the numbers were small, the patterns of responders was highly
favorable for the combined Androxal group over the placebo group (p =
0.002, Chi2) and over the Androgel group (p = 0.027, Chi2).
If values for fasting plasma glucose can be lowered over a sustained
period of time, similar positive changes in glycemic control through
parameters such as HbA1c may be seen. Clearly, the larger
proposed prospective trial in a T2D group matched for initial HbA1c
followed over an extended period of time could provide the chance to
test these findings more definitely.
At this point, secondary hypogonadism is presumed to play a role in the
process. The relationship of testosterone to metabolism is complex and
hypogonadism may be critical to certain components of a healthy man’s
lifestyle. In a recent series of reviews in the Journal of Andrology
by Traish, Saad, Feeley, and Guay, the authors traced out the “The Dark
Side of Testosterone Deficiency” as it applies to metabolic syndrome,
erectile dysfunction, diabetes, insulin resistance, and cardiovascular
disease. In the second of their reviews (Traish, Saad, and Guay, J
Androl 2009 30(1), 23-32) they commented that “T plays a crucial
role in maintaining metabolic homeostasis; thus, this hormone may play a
vital role in maintaining glycemic control.” They went on to add that,
“T therapy may provide protective effects against the onset of diabetes
or may ameliorate the pathology of diabetic complications.” Work of
Pitteloud et al suggests that the effects are just not
testosterone related but closely tied to restimulation of Leydig cell
synthesis of testosterone. There is good evidence from the work
of Pitteloud et al (J Clin Endocrionl Metab 2005 90(5);
2636-2641) that insulin resistance is associated with a decrease in
Leydig cell testosterone secretion.
Joseph S. Podolski, President and CEO of Repros noted, “The
retrospective analysis from our previous study is interesting. However
we should not underestimate the challenges in conducting studies in
diabetes. We believe the protocol we have designed will determine if
there is clinically significant signal that warrants further
development.” He commented further that before proceeding with the study
the Company must raise additional capital and is currently evaluating
several different financing options.