Veozah (Fezolinetant) Titration in Renal Impairment: A Complete Guide for Women

What Renal Impairment Means for Veozah Dosing

Fezolinetant is primarily metabolized by the liver via CYP1A2 and CYP2C19, but renal clearance still contributes to overall drug elimination. When your kidneys are not filtering at full capacity, fezolinetant and its active metabolite (ES259564) can accumulate, raising the risk of liver enzyme elevations and other adverse effects.

The FDA-approved prescribing information specifies three tiers of renal function, measured by estimated glomerular filtration rate (eGFR):

• eGFR 60 to 89 mL/min/1.73 m² (mild impairment): standard 45 mg dose is permitted, with routine monitoring
• eGFR 30 to 59 mL/min/1.73 m² (moderate impairment): maximum dose capped at 30 mg once daily
• eGFR below 30 mL/min/1.73 m² (severe impairment or ESKD): Veozah is contraindicated

Why the Dose Cap Matters at eGFR 30-59

At moderate renal impairment, population pharmacokinetic modeling showed that fezolinetant exposure (AUC) rises meaningfully compared with normal renal function. The 30 mg cap is designed to keep total drug exposure within the range studied in the SKYLIGHT trials without exceeding the safety thresholds established for liver toxicity.

How Your Prescriber Determines Your eGFR

Your eGFR is calculated from a blood creatinine level, your age, and sex. Women typically have lower serum creatinine at any given kidney function level than men do, because we carry less muscle mass. This means a creatinine that looks "normal" on a lab report may still correspond to a clinically significant eGFR reduction, particularly after age 50 when muscle mass declines further. Ask your provider to run a full metabolic panel and calculate your CKD-EPI eGFR before starting Veozah.

The SKYLIGHT Trials: What the RCT Data Show

The two key phase 3 studies, SKYLIGHT 1 and SKYLIGHT 2, enrolled postmenopausal women aged 40 to 65 with moderate-to-severe vasomotor symptoms and randomized them to fezolinetant 30 mg, fezolinetant 45 mg, or placebo for 12 weeks, with a 40-week safety extension. Both trials excluded women with eGFR below 30 mL/min/1.73 m², which is why severe renal impairment remains contraindicated: there are simply no human safety data in that population.

Efficacy Across Doses

At week 12, fezolinetant 45 mg reduced mean daily moderate-to-severe VMS frequency by approximately 60% from baseline compared with roughly 45% for placebo. The 30 mg dose produced numerically similar reductions, suggesting that the lower dose used in moderate renal impairment is not expected to substantially compromise efficacy.

Liver Safety Signal: The Detail Every Woman With Kidney Disease Needs

The SKYLIGHT 4 safety extension trial (52 weeks) identified aminotransferase elevations above three times the upper limit of normal in 2.3% of fezolinetant-treated women versus 0.7% on placebo. This is why liver monitoring applies to every woman on Veozah regardless of kidney status, but women with renal impairment face compounded concern: reduced renal clearance of metabolites can shift the metabolic burden further onto hepatic pathways.

The FDA label requires liver function tests at baseline and at 3 and 6 months after starting treatment. If ALT or AST rises above five times the upper limit of normal, Veozah must be discontinued immediately.

Life-Stage Context: Who Is Actually Taking Veozah

Veozah is approved only for menopausal vasomotor symptoms, so the women who take it are, by definition, either perimenopausal or postmenopausal. Kidney function and life stage are deeply connected here.

Perimenopause (Typically Ages 45-55)

EGFR tends to be closer to normal in this group, but conditions common in midlife women (hypertension, type 2 diabetes, PCOS-related insulin resistance) can already be silently eroding kidney function. CKD affects approximately 14% of the US adult population, and women with a history of PCOS, gestational hypertension, or preeclampsia face elevated lifetime risk of chronic kidney disease. A baseline eGFR check is not optional in this group.

Postmenopause (Ages 55 and Beyond)

After menopause, estrogen loss accelerates cardiovascular and renal aging. Postmenopausal women with longstanding hypertension or diabetes are more likely to have eGFR in the moderate impairment range without knowing it. The Menopause Society (formerly NAMS) 2023 position statement identifies non-hormonal pharmacotherapy as an appropriate option for women who cannot or choose not to use hormone therapy, placing fezolinetant squarely in the decision framework for postmenopausal women with comorbidities including renal disease.

The table below maps life stage to the practical renal monitoring approach a woman and her clinician should follow before and during Veozah therapy.

| Life Stage | Typical eGFR Concern | Recommended Pre-Start Check | Monitoring Frequency | |---|---|---|---| | Perimenopause (45-55) | Usually normal; screen if hypertension, DM, PCOS | BMP or CMP with eGFR calculation | Annually or per CKD guidelines | | Early postmenopause (55-65) | Mild decline possible | BMP or CMP with eGFR | Every 6-12 months | | Late postmenopause (65+) | Moderate decline more common | BMP or CMP with eGFR | Every 3-6 months; adjust dose if eGFR drops |

Pregnancy, Lactation, and Contraception

Veozah is not for use during pregnancy. Fezolinetant is indicated only for menopausal vasomotor symptoms, a population that by definition has experienced menopause. However, perimenopause is not reliable contraception. Women in the menopausal transition can still ovulate sporadically, and ACOG confirms that contraception should be considered until 12 consecutive months of amenorrhea have been confirmed.

Pregnancy Category and Human Data

The FDA fezolinetant prescribing information states there are no adequate human data on the use of fezolinetant in pregnant women to evaluate for drug-associated risk of major birth defects, miscarriage, or other adverse maternal or fetal outcomes. Animal reproductive toxicity studies showed embryofetal effects at doses higher than clinical exposure, which is a reason for caution even in the absence of definitive human teratogenicity data.

Lactation

There are no data on fezolinetant presence in human breast milk, effects on the breastfed infant, or effects on milk production. The developmental and health benefits of breastfeeding should be considered alongside the mother's clinical need and any potential adverse effects. Given the absence of safety data, avoiding Veozah during lactation is the recommended approach.

Contraception Requirement for Perimenopausal Women

A perimenopausal woman prescribed Veozah who has not yet reached 12 months of confirmed amenorrhea should use effective contraception. This matters doubly if she has renal impairment: pregnancy in the setting of CKD carries substantially elevated risks for both mother and fetus. If pregnancy occurs during treatment, Veozah should be stopped immediately and the prescriber notified.

Drug Interactions That Compound Renal Risk

Women with kidney disease are frequently on multiple medications, and fezolinetant's CYP1A2 and CYP2C19 metabolic pathways create meaningful interaction risks.

CYP1A2 Inhibitors

Strong CYP1A2 inhibitors such as fluvoxamine significantly increase fezolinetant exposure. The FDA label contraindicates co-administration of strong CYP1A2 inhibitors with fezolinetant. Women with CKD who are also on fluvoxamine for depression or anxiety should not use Veozah.

Nephrotoxic Co-Medications

Many drugs commonly used in women with CKD (NSAIDs, certain antibiotics, contrast agents) can acutely worsen renal function and drop an eGFR from a "moderate impairment" tier into the "severe impairment" contraindicated range. If you are taking Veozah at the 30 mg dose for moderate CKD, any new nephrotoxic medication exposure should prompt an eGFR recheck before continuing fezolinetant.

Hormone Therapy Interactions

Women who combine fezolinetant with systemic hormone therapy are not well-studied in the renal impairment subgroup. Estrogen-containing hormone therapy has its own renal and hepatic metabolic implications and may independently affect CYP enzyme activity. This combination should be managed in consultation with a specialist familiar with both menopause pharmacology and renal function.

Who This Is Right For, and Who Should Look Elsewhere

Women Who May Benefit Most

• Postmenopausal women with mild-to-moderate CKD (eGFR 30-89) who have moderate-to-severe hot flashes and cannot use or prefer to avoid hormone therapy
• Women with a history of hormone-receptor-positive breast cancer where estrogen is contraindicated, provided their eGFR permits the appropriate dose
• Women with PCOS-related metabolic comorbidities who have developed mild renal impairment and need non-hormonal VMS relief

The 2023 Menopause Society clinical practice guidelines specifically list fezolinetant as a recommended non-hormonal option with the highest level of evidence for VMS frequency and severity reduction.

Women Who Should Not Use Veozah

• eGFR below 30 mL/min/1.73 m² (severe impairment or ESKD): contraindicated
• Active liver disease or unexplained persistent liver enzyme elevations: contraindicated
• Women taking strong CYP1A2 inhibitors: contraindicated
• Pregnant women or those who may become pregnant: not indicated
• Women with known cirrhosis or moderate-to-severe hepatic impairment: contraindicated

Monitoring Schedule: A Practical Checklist

Because renal impairment and hepatic risk intersect in Veozah users, monitoring is more layered than for a healthy postmenopausal woman with normal kidney function.

Before Starting

1. Measure serum creatinine, calculate CKD-EPI eGFR
2. Obtain baseline ALT, AST, alkaline phosphatase, and total bilirubin
3. Review the full medication list for CYP1A2 inhibitors or nephrotoxic drugs
4. Confirm menopausal status (12 months amenorrhea) or, if perimenopausal, confirm contraception plan
5. Document VMS frequency and severity using a validated tool (e.g., Menopause-Specific Quality of Life questionnaire)

At 3 Months

• Repeat liver function panel (ALT, AST, ALP, bilirubin): required by FDA label
• Recheck eGFR if any intercurrent illness, new medication, or clinical change occurred
• Assess VMS response: SKYLIGHT 1 showed statistically significant VMS reduction by week 4, so lack of any benefit at 3 months warrants reassessment

At 6 Months

• Final required liver function check per label
• Full eGFR reassessment, especially in women aged 65 and older or those with progressive CKD diagnoses
• Re-evaluate dose: if eGFR has fallen from the 60-89 range into the 30-59 range since starting, a dose reduction from 45 mg to 30 mg is warranted immediately

Ongoing (Every 6-12 Months)

• Annual or semi-annual eGFR per CKD monitoring standards
• Liver enzymes if any new symptoms (jaundice, right upper quadrant pain, fatigue, dark urine) develop
• VMS reassessment to confirm continued therapeutic benefit

Sex-Specific Pharmacokinetics: What Women Need to Know

Women generally have lower CYP1A2 activity than men, and oral contraceptives and estrogen-containing hormone therapy further suppress CYP1A2. Population pharmacokinetic analyses of fezolinetant included only women, which is a strength of the trial program but also means all PK data are female-specific by default.

The key practical implication: a woman transitioning off estrogen-containing hormone therapy to start fezolinetant may experience a modest shift in CYP1A2 activity as exogenous estrogen is withdrawn. This transition period should be flagged to the prescriber, particularly in women with moderate renal impairment where the pharmacokinetic margin is already narrower.

Women also clear creatinine differently than men at equivalent kidney function levels, as noted above. Because CKD-EPI equations are sex-adjusted, the eGFR calculation already accounts for this, but it is a reason not to rely on serum creatinine alone when assessing renal function before prescribing.

The Evidence Gap Women Deserve to Know About

The SKYLIGHT program enrolled women who were overwhelmingly healthy at baseline, with the renal impairment subgroup being small. Women with CKD have historically been underrepresented in menopause pharmacology trials, and there are no published subgroup analyses specifically reporting VMS efficacy outcomes stratified by eGFR tier.

What this means for you: the 30 mg dose recommendation for moderate CKD is based on pharmacokinetic modeling and safety extrapolation, not a large randomized trial of women with eGFR 30-59 who were followed for 52 weeks. The dose is rational and the FDA has approved it, but your prescriber should be honest with you that real-world outcome data in this subgroup are thin.

Women with moderate CKD who start Veozah at 30 mg are, in a meaningful sense, at the clinical frontier of this drug's use. Reporting any adverse effects to your provider promptly matters not just for your own care but for the broader evidence base.

Switching From Other VMS Treatments in the Setting of Renal Impairment

From SSRIs/SNRIs

Paroxetine (Brisdelle) is the only FDA-approved non-hormonal VMS treatment other than fezolinetant, but it requires dose adjustment in renal impairment and carries its own drug interaction profile. ACOG Practice Bulletin 141 notes SSRIs and SNRIs as second-line non-hormonal options. Switching from paroxetine to fezolinetant requires a washout period in women also taking any CYP1A2-sensitive medications. Both agents require eGFR assessment before and during use.

From Hormone Therapy

Women discontinuing systemic HT to start fezolinetant may experience a temporary rebound increase in VMS frequency during the transition. The Menopause Society recommends tapering HT rather than abrupt discontinuation where possible, especially in women with renal impairment where hormonal changes can have hemodynamic effects on kidney perfusion.

From Gabapentin

Gabapentin is commonly used off-label for VMS in women who cannot use estrogen and requires substantial dose reduction in renal impairment. Transitioning to fezolinetant may allow a cleaner pharmacological profile with fewer CNS side effects, provided the eGFR permits use.