ESTROGEN PREPARATIONS FOR HORMONE REPLACEMENT THERAPY
n.b. naturally occurring human estrogens = estrone,
estradiol, estriol
I Oral--Extensive first-pass, so liver is exposed to
higher levels than peripheral blood; this may be a reason for pro-coagulant and lipid-altering effects
- Conjugated equine estrogens (Premarin) 0.3 -1.25mg PO QD
- Has most long-term data available
- 50% estrone, 25% equiline, and others
- Dosing
- In estrogen-only (no progestin) HRT, reduction in vasomotor
symptoms was sig. better with 0.625mg CEE than with
lower doses but in combined estrogen-progestin HRT, all
doses were equally good (0.3-0.625mg/d) in a randomized
trial in 2673 postmenopausal women. Lower doses of
CEE were ass'd with higher rates of amenorrhea in both
estrogen-only and combined HRT regimens (Fertil. Steril.
75:1080, 2001--JW)
- Esterified estrogents (Estratab, Menest)
- Conjugated estrogen, synthetic (Cenestin, Enjuvia)
0.625-1.25mg PO QD
- Estradiol valerate (Estrace) 1-2mg PO QD
- Metabolized to estrone
- Estropipate 0.625-5mg PO QD
- Estradiol/estrone/estriol mixture (used mostly in
Europe)
- "Selective Estrogen Receptor
Modulators"--designed to act on lipids &
bone but not breast or uterus
- Tamoxifen--has significant action on
uterus in addition to bone & lipids;
acts as an estrogen antagonist in breast
tissue
- Raloxifene (Evista) 60mg
QD
- Acts as estrogen agonist bone
& lipids but antagonist on
breast & endometrium
- Increases bone density and
decreases risk of vertebral fx
- Greater increase
c/w placebo in
postmenopausal but less
in historical comparisons
than Premarin (NEJM
337:1641, 1997)
- 7705 women
31-80yo, 37% with
existing vertebral fx,
all at least 2y post
menopause, with
osteoporosis, randomized
to Raloxifene 120mg/d,
60mg/d, or placebo; all
got Ca & vit. D. Over
3y f/u, RR of vertebral
fx c/w placebo was 0.7
for 60mg group and 0.5
for 120mg group (both
sig.); no sig. effect on
risk of nonvertebral
fracture
("MORE" study,
JAMA 282:637, 1999--abst)
- Effects on endometrium
- No diff. in endometrial
thickness between
raloxifene and placebo
group (NEJM 337:1641,
1997)
- No diff. in incidence of
endometrial Ca in 40mo
trial c/w placebo (JAMA
281:2189, 1999)...
- ...or in a 3.3y study of Raloxifene 60-120mg/d vs. placebo (Multiple Outcomes
of Raloxifene Evaluation
("MORE") Trial; Obs. Gyn.
104:837, 2004--JW)
- Effects on cardiovascular disease & risk factors
- Raloxifene ass'd with
decrease in total and LDL
cholesterol c/w placebo
but no change in HDL
(NEJM 337:1641, 1997)
- 390 women assigned to raloxifene, combined HRT,
or placebo x 6mos. Raloxifene and HRT groups
showed similar reductions
in LDL; raloxifene ass'd
with sig. less
improvement in HDL and
lipoprotein (a) c/w HRT
(JAMA 279:1445, 1998)
- In a secondary analysis of the MORE
study data (done primarily to assess
effects of Raloxifene in breast Ca
reduction), pts receiving Raloxifene 60mg
QD vs.
placebo had similar risk for fatal or
nonfatal cardiovascular events; in
subgroup of 1035 women with high CV risk
(prior coronary event or DM + one other
cardiac risk factor), Raloxifene was ass'd
with sig. lower risk (8% vs. 13% over 4y
f/u) (JAMA 287:847, 2002--JW)
- 390 healthy postmenopausal women
randomized to: a. Raloxifene 60mg/d; b. Raloxifene 120mg/d; c. premarin 0.625 + provera
2.5/d; d. placebo. After 6mos f/u, LDL levels
were down 12% in both raloxifene groups c/w 14%
in standard HRT group. Lipoprotein (a) was down
7-8% with raloxifene c/w 19% with standard HRT.
HDL-2 was up 15-17% with raloxifene c/w 33% with
standard HRT. No sig. change in total HDL, TG, or
plasminogran activator inhibitor-1 with raloxifene, while standard HRT increased HDL by
11%, TG 20%, and PAI-1 by 29%. Fibrinogen was
down 12-14% with raloxifene; no effect with
standard HRT (JAMA 279:1445, 1998--abst)
- In a study in 10,101 postmenopausal
women at high risk for CAD randomized to raloxifene
60mg/d vs. placebo, after
median 5.6y f/u, incidence of
(cardiovascular death, MI, or
hospitalization for acute coronary
syndrome) was not sig. diff. between the
two groups (for overall cohort + various
subgroups). Raloxifene recipients had sig.
lower incidence of breast Ca. (0.20% vs.
0.29%) and fewer vertebral fractures
("Raloxifene Use for The Heart"
("RUTH") Trial NEJM 355:125,
2006--JW)
- Prevention of Breast
Cancer--Click link for details
- Venous
thromboembolism--ass'd with
increased risk
- RR 3.0 in one
study (JAMA 281:2189,
1999)
- RR 3.1 (sig.) in
the first MORE trial (see
above)
- In a trial in 7,705
postmenopausal women (31-80yo) with
osteoporosis randomized to raloxifene 60-120mg/d vs. placebo, over mean 3.3y
f/u, raloxifene was ass'd with RR 2.1
(sig.) for venous thromboembolism
(absolute risk increase 1.8 events per
1,000 person-years of use); no sig. diff.
in risk for gallbladder disease,
endometrial Ca, or cataracts (Multiple
Outcomes of Raloxifene Evaluation
("MORE") Trial; Obs. Gyn.
104:837, 2004--JW)
- The Factor
V Leiden mutation was associated with
sig. increase in risk (OR 4.7) of venous
thromboembolism in a case-control study
women with breast Ca on tamoxifen (J. Nat.
Ca. Inst. 102:942, 2010-JW)
- Overall risk of Cancer: No increase
seen in studies w/up to 3y f/u
(Med. Letter 40:30, 1998)
- Other adverse effects:
- Hot flashes
- Flu-like syndrome
- Left cramps
- Peripheral edema
- Diabetes
Mellitus (RR 2.2 for
new or worsening DM in
40mo f/u, although there
was no diff. in median
changes in fasting plasma
glucose or HbA1c--JAMA
281:2189, 1999)
- May decrease effect of warfarin
- Does not cause resumption of
menses as does estrogen therapy
- Bazedoxifene
- Associated with no sig. diff. in changes in
endometrial thickness or incidence of breast Ca
compared with both raloxifene and placebo in several
randomized trials with durations of up to 2 years
(Menopause 16:1102, 2009; Menopause 16:1116, 2009-JW)
II. Parenteral
- Advantages over oral
- Less effect on thrombotic state because of no
"first-pass" effect--See below for
details
- Better in pts with stable liver disease
- Available preparations:
- Transdermal estradiol 0.05-0.1mg 2x/wk
- Subcutaneous estradiol pellets (not good;
fluctuating absorption as of 1994)
- Estradiol vaginal pessaries or rings
III. Topical-Used primarily to relieve symptoms due to urogenital atrophy