Jatenzo in Adults 65 and Older: Off-Label Use, Risks, and Clinical Guidance

What "Off-Label" Means for Jatenzo in Men Over 65

Jatenzo received FDA approval in March 2019 specifically for men with classical or biochemical hypogonadism caused by a known medical condition, such as primary hypogonadism or hypothalamic-pituitary axis failure. The label does not define a geriatric dosing schedule, exclude older men, or include outcomes data from randomized trials conducted exclusively in men over 65. [1]

Using Jatenzo in a 68-year-old with an age-related testosterone decline of 250 ng/dL therefore sits outside the approved indication. The prescriber carries full clinical and legal responsibility for that decision.

Why Age-Related Decline Is Treated Differently

Serum testosterone falls roughly 1 to 2% per year after age 30 in men. [2] By age 70, a substantial proportion of men have total testosterone below 300 ng/dL, which meets many laboratory definitions of hypogonadism. The 2018 Endocrine Society Clinical Practice Guideline states: "We suggest against making a general recommendation for or against testosterone therapy in all older men with low testosterone levels." [3] The guideline draws a sharp line between biochemical hypogonadism caused by identifiable pathology and the gradual physiological decline of aging.

That distinction matters for Jatenzo specifically. Prescribers who document a structural cause (such as prior orchiectomy, Klinefelter syndrome, or pituitary adenoma) have a cleaner regulatory and ethical foundation than those treating a 67-year-old whose total testosterone of 265 ng/dL reflects nothing beyond age.

The Testosterone Trials (TTrials) and What They Found

The Testosterone Trials (TTrials) remain the most cited dataset on TRT in older men. Seven coordinated trials enrolled 788 men aged 65 and older with total testosterone below 275 ng/dL. [4] The sexual-function trial showed modest improvement in libido and erectile function scores. The physical-function trial found no significant difference in walking distance. The bone trial showed increased volumetric bone mineral density, but fracture events were not reduced. [4]

Critically, the TTrials used transdermal testosterone gel, not oral testosterone undecanoate. Extrapolating TTrials efficacy data to Jatenzo assumes bioavailability equivalence, which has not been demonstrated in a head-to-head geriatric comparison. [5]

FDA Label Warnings That Apply With Greater Force After Age 65

The FDA prescribing information for Jatenzo includes a dedicated cardiovascular warning. The label notes that testosterone products may increase the risk of major adverse cardiovascular events (MACE), and the agency has required all testosterone manufacturers to conduct post-market studies evaluating long-term cardiovascular outcomes. [1]

Blood Pressure Elevation

In the key Jatenzo phase 3 trial (N=166, 16-week open-label), mean systolic blood pressure rose 3.5 mmHg and mean diastolic blood pressure rose 2.0 mmHg from baseline. [6] Hypertension prevalence in men over 65 in the United States exceeds 70% according to CDC NHANES data. [7] That baseline burden means a 3 to 5 mmHg systolic increase carries materially higher absolute risk in an older cohort than in a younger one.

Clinicians prescribing Jatenzo to men over 65 should measure blood pressure at every visit for the first six months, then at minimum every three months. Any systolic reading consistently above 130 mmHg per the 2017 ACC/AHA guideline threshold warrants treatment adjustment before continuing testosterone. [8]

Hematocrit and Venous Thromboembolism

Testosterone stimulates erythropoiesis. The Jatenzo label specifies that hematocrit should be checked at baseline, at 3 to 6 months, and annually. [1] If hematocrit exceeds 54%, the drug should be withheld until levels fall below 50%, then restarted at a lower dose or discontinued. Older men with pre-existing polycythemia vera, chronic obstructive pulmonary disease, or residence at high altitude begin at elevated erythrocytic baselines, compressing the margin before the 54% ceiling. [9]

Venous thromboembolism (VTE) risk in men 65 and older is already higher than in younger cohorts. The 2014 FDA Drug Safety Communication on testosterone and VTE emphasized that this risk applies to all testosterone formulations. [10]

Prostate Safety

The Jatenzo label requires a baseline PSA measurement before starting therapy and a digital rectal exam or PSA recheck within 3 to 6 months of initiation. [1] Men over 65 carry the highest baseline burden of undiagnosed prostate cancer. The American Cancer Society estimates that 60% of all prostate cancer diagnoses occur in men 65 and older. [11]

A rise in PSA of more than 1.4 ng/mL above baseline during any 12-month period, or a single PSA above 4.0 ng/mL, should prompt urology referral before continuing Jatenzo. Subclinical prostate cancer stimulated by exogenous testosterone in an unscreened 70-year-old represents one of the clearest harms associated with off-label use in this age group.

Pharmacokinetics in Older Adults

Oral testosterone undecanoate is absorbed via intestinal lymphatics, bypassing first-pass hepatic metabolism. This is pharmacologically meaningful because older men have reduced hepatic blood flow and lower CYP enzyme activity. [12] Jatenzo's lymphatic absorption route reduces (but does not eliminate) the hepatotoxicity risk that characterized 17-alpha-alkylated oral androgens, and the reduced hepatic dependence may be a modest advantage in men with mild hepatic impairment from age-related changes. [1]

Absorption Requires Dietary Fat

Jatenzo must be taken with a fat-containing meal. In phase 3 studies, co-administration with a high-fat meal (approximately 50 g of fat) produced testosterone Cmax values 4-fold higher than fasting administration. [6] Older adults with reduced appetite, early satiety, or following low-fat dietary prescriptions for cardiovascular disease may not consistently achieve this fat threshold. Inconsistent fat intake produces erratic serum testosterone levels and unreliable dose titration.

Clinicians should confirm dietary habits during the intake visit and counsel specifically about the fat requirement with each meal that accompanies the dose.

Drug Interactions in a Polypharmacy Population

Men over 65 take an average of 4.5 prescription medications. [13] Testosterone is a known inhibitor of CYP2C19 and can potentiate anticoagulants (warfarin INR may rise), insulin (hypoglycemic episodes may increase), and corticosteroids (fluid retention risk compounds). [1] A full medication reconciliation is mandatory before initiating Jatenzo in any patient over 65, and INR should be rechecked within 2 to 4 weeks of any dose change in men taking vitamin K antagonists.

Dosing Protocol for Off-Label Geriatric Use

The FDA-approved adult dosing schedule begins at 158 mg twice daily with food. A serum testosterone drawn 6 hours after the morning dose at approximately week 6 guides titration. [1]

Titration Steps

If the 6-hour post-dose testosterone is below 400 ng/dL, the dose increases to 237 mg twice daily. A second check at week 12 may prompt a further increase to 316 mg or the maximum of 396 mg twice daily. If the 6-hour value exceeds 800 ng/dL, the dose decreases one step. [1]

No geriatric-specific titration adjustment exists in the label. Some clinicians advocate for a lower initial target (400 to 600 ng/dL rather than 400 to 700 ng/dL) in men over 65, accepting the lower end of the normal range to reduce cardiovascular and erythrocytic pressure, but this represents clinical opinion rather than guideline-endorsed practice. [3]

Monitoring Schedule for Men Over 65

The following schedule extends the label's minimum requirements to address the added risks of age:

• Baseline: total testosterone, free testosterone, hematocrit, PSA, comprehensive metabolic panel, blood pressure, fasting lipids, BMI
• Week 6: serum testosterone at 6 hours post-dose, blood pressure
• Week 12: hematocrit, blood pressure, dose-titration testosterone if not yet at goal
• Month 6: PSA, hematocrit, lipid panel, blood pressure, symptom review
• Annually: all of the above plus DXA bone density if osteopenia was present at baseline

Cardiovascular Risk: What the Data Actually Show

The cardiovascular signal around testosterone therapy in older men remains unresolved. The TRAVERSE trial (N=5,246, mean age 63.3 years) compared testosterone gel versus placebo in men with hypogonadism and established or high cardiovascular risk. [14] Non-inferiority was met for MACE (HR 0.96, 95% CI 0.78 to 1.17), meaning testosterone did not significantly increase heart attacks or strokes relative to placebo over a mean follow-up of 33 months. [14]

However, TRAVERSE also found a statistically significant increase in nonfatal arrhythmia events and pulmonary embolism in the testosterone arm, with a hazard ratio for pulmonary embolism of 1.92 (P<0.05). [14] These findings appeared in men whose mean age was 63, below the 65-and-older threshold under discussion here, and the trial used transdermal gel rather than oral testosterone undecanoate.

Applying TRAVERSE reassurance to Jatenzo in men aged 70 to 80 requires two layers of extrapolation: formulation difference and age difference. Neither is supported by direct trial data. A 2020 meta-analysis published in JAMA Internal Medicine that analyzed 11 randomized controlled trials found that cardiovascular event risk with testosterone was elevated in older men (relative risk 1.54 for men over 65 vs. No significant increase in men under 55). [15]

Atrial Fibrillation Specifically

TRAVERSE identified a higher rate of atrial fibrillation in the testosterone arm (HR 1.30, P<0.05). [14] Atrial fibrillation prevalence in men over 65 already exceeds 9% in population surveys. [16] A clinician prescribing Jatenzo to a 68-year-old man with pre-existing paroxysmal atrial fibrillation should document the added risk explicitly and consider cardiology co-management.

Bone Density: A Potential Benefit, Not a Clear Indication

Osteoporosis affects approximately 5 to 6% of men over 65, and osteopenia affects an additional 47%. [17] Low testosterone is one documented contributor to male osteoporosis. The TTrials bone sub-trial showed that testosterone gel increased estimated bone strength at the spine and hip at 12 months in men 65 and older with baseline testosterone below 275 ng/dL. [4]

This finding is relevant but insufficient to justify Jatenzo as a primary osteoporosis treatment. The National Osteoporosis Foundation and the Endocrine Society identify bisphosphonates (alendronate, zoledronic acid) as first-line agents for male osteoporosis. [17] Jatenzo does not carry an osteoporosis indication. Using it primarily for bone density in an older man who lacks symptomatic hypogonadism would represent a second layer of off-label use stacked on the first.

If a prescriber is managing an older man who has both symptomatic hypogonadism and osteoporosis, documenting both conditions and co-prescribing a bisphosphonate while monitoring DXA at 12 months is a clinically defensible strategy.

Cognitive Function and Mood: Limited Evidence in This Formulation

Testosterone's role in cognition in older men has attracted substantial research interest. The TTrials cognitive sub-trial found no significant effect on cognitive function in men 65 and older treated with testosterone gel versus placebo over 12 months, using the Cognitive Function Instrument and several neuropsychological tests. [18]

A 2019 Cochrane systematic review of testosterone for cognitive function in older men concluded that existing evidence is insufficient to confirm or refute a meaningful benefit. [19] No published data examine Jatenzo's specific formulation in any cognitive outcome trial. Prescribers who cite cognitive benefit as a rationale for off-label Jatenzo in men over 65 are working without clinical trial support for that specific claim.

Mood improvement is a more consistently reported subjective benefit of TRT in hypogonadal men. The TTrials vitality sub-trial showed a modest improvement in sexual desire scores but no significant improvement on the SF-36 vitality scale in men 65 and older with low testosterone. [4] Modest mood or energy benefit may exist, but it does not resolve the risk calculus for an individual patient.

Informed Consent: What the Conversation Must Cover

Off-label prescribing is legal and sometimes clinically appropriate. The ethical obligation is a documented informed-consent discussion that covers the following specific points for men over 65 considering Jatenzo:

1. Jatenzo is not FDA-approved with a geriatric-specific label or dosing guideline.
2. Long-term cardiovascular trial data in men over 65 using oral testosterone undecanoate specifically do not exist.
3. PSA and prostate cancer risk will be monitored but cannot be fully excluded.
4. Blood pressure will likely rise modestly. Existing antihypertensive regimens may need adjustment.
5. Hematocrit monitoring is required. Stopping or reducing dose may be necessary.
6. Drug interactions with warfarin, insulin, or corticosteroids require closer monitoring of those therapies.
7. The patient should report any new palpitations, leg swelling, or shortness of breath immediately.

The Endocrine Society guideline specifies: "Clinicians should discuss with patients the uncertainty about the risks and benefits of testosterone therapy." [3] That instruction applies with amplified force when the patient is over 65 and the use is off-label.

When Jatenzo May Be Reasonable in a Patient Over 65

Jatenzo may be a reasonable choice in the following clinical scenarios:

• A man 65 to 70 years old with documented primary hypogonadism (confirmed low morning testosterone on two occasions, documented testicular failure), who has tried transdermal testosterone and experienced persistent skin-application site reactions or subtherapeutic absorption.
• A man with a pituitary tumor that has caused secondary hypogonadism, who has difficulty with daily transdermal application and prefers an oral formulation.
• A man who has completed prostate cancer treatment (with urology and oncology sign-off), whose total testosterone is severely suppressed, and who has symptomatic hypogonadism impairing quality of life.

Jatenzo is unlikely to be appropriate as a first-line choice in men over 65 when the only indication is age-related testosterone decline without structural diagnosis, when the man has uncontrolled hypertension (systolic above 160 mmHg), active cardiovascular disease within 6 months, hematocrit above 50% at baseline, untreated or undertreated sleep apnea, active or suspected prostate cancer, or a PSA above 4.0 ng/mL without prior urology evaluation. [1] [3]

Alternatives to Jatenzo for Hypogonadal Men Over 65

When TRT is warranted but Jatenzo's oral route, fat-absorption requirement, or blood pressure profile creates concern, other formulations deserve consideration:

Testosterone cypionate intramuscular injection (100 to 200 mg every 1 to 2 weeks) has decades of use data, predictable pharmacokinetics, and no fat-dependent absorption. [20] Testosterone gel 1.62% (AndroGel) provides stable daily delivery with well-characterized data from the TTrials. [4] Testosterone nasal gel (Natesto, 11 mg three times daily) produces the lowest hematocrit increases of any available formulation, making it potentially preferable in older men near the erythrocytic threshold. [21]

No head-to-head trial has compared these formulations specifically in men over 65 for cardiovascular outcomes, bone density, or quality of life.