Farxiga vs Tresiba: Cost, Access, and Which Is Right for You

What Are These Two Drugs and Why Are Women Comparing Them?

Farxiga and Tresiba sit in completely different drug classes, yet women with type 2 diabetes are frequently weighing one against the other because both lower blood glucose and both carry significant costs. Understanding what each drug actually does is the starting point.

Dapagliflozin (Farxiga) blocks the SGLT2 transporter in the kidney, causing excess glucose to spill into the urine. It lowers A1C by roughly 0.5 to 1.0 percentage points, produces modest weight loss of 2 to 3 kg on average, and reduces blood pressure slightly. Critically, it has FDA-approved indications beyond diabetes: heart failure with reduced ejection fraction (HFrEF), heart failure with preserved ejection fraction (HFpEF), and chronic kidney disease (CKD).

Insulin degludec (Tresiba) is a basal insulin with an ultra-long half-life of more than 25 hours. It provides the background insulin needed to keep fasting glucose stable. It is the only option when the pancreas cannot produce enough insulin, as in type 1 diabetes. For type 2 diabetes, it is added when oral agents alone no longer control glucose adequately.

These two drugs are not interchangeable for most patients. A woman with type 1 diabetes cannot drop Tresiba for Farxiga. But a woman with type 2 diabetes, preserved kidney function, and early cardiovascular risk may find that Farxiga offers comparable glucose control plus organ-protective benefits that Tresiba does not.

How Each Drug Performed in Its Landmark Trial

No direct head-to-head trial of dapagliflozin versus insulin degludec exists. The comparison here is cross-trial and should be read with that limitation clearly in mind.

DAPA-HF: Farxiga's Defining Cardiovascular Trial

The DAPA-HF trial (NEJM 2019) enrolled 4,744 adults with HFrEF (ejection fraction <40%) and randomized them to dapagliflozin 10 mg daily or placebo on top of standard heart-failure therapy. Dapagliflozin produced a 26% relative reduction in the composite of worsening heart failure or cardiovascular death compared with placebo. Women made up only 23% of DAPA-HF participants, a limitation the trialists acknowledged. Subgroup analyses did not show a statistically significant difference by sex, but the absolute data in women specifically remain thin.

DEVOTE: Tresiba's Non-Inferiority Cardiovascular Trial

The DEVOTE trial (NEJM 2017) compared insulin degludec with insulin glargine U100 in 7,637 adults with type 2 diabetes at high cardiovascular risk. Degludec was non-inferior to glargine on three-point MACE (cardiovascular death, non-fatal MI, non-fatal stroke), with a hazard ratio of 0.91 (95% CI 0.78 to 1.06). Degludec also produced significantly less nocturnal symptomatic hypoglycemia than glargine, a 53% lower rate that is directly relevant to women who manage overnight feeding, caregiving, or shift work.

DEVOTE did not include a placebo or a non-insulin comparator, so it does not tell us whether degludec prevents cardiovascular events better than oral agents in women with moderate-risk type 2 diabetes.

What the Cross-Trial Picture Tells You

Farxiga has active cardiovascular and renal benefits beyond glucose lowering. Tresiba has a lower hypoglycemia burden compared to glargine but does not demonstrate active cardiovascular protection beyond non-inferiority. For a woman with type 2 diabetes plus heart failure or CKD, Farxiga's label now covers those conditions directly. Tresiba remains the backbone for anyone who needs exogenous basal insulin to survive or to prevent diabetic ketoacidosis.

Cost and Access: The Real-World Numbers

List Price vs. What You Actually Pay

Costs below are US list prices as of early 2025. Your actual out-of-pocket depends on insurance, copay cards, and income-based programs.

| | Farxiga (dapagliflozin) | Tresiba (insulin degludec) | |---|---|---| | Typical list price | ~$600/month (10 mg, 30 tablets) | ~$400-$550/month (FlexTouch pen, 5x3 mL) | | Manufacturer savings card | AstraZeneca: $0 copay for eligible commercially insured patients | Novo Nordisk: NovoCare program; $99/month cap for uninsured qualifying patients | | Medicare Part D | Covered on most formularies, Tier 3-4 | Covered on most formularies, Tier 2-3 | | Generic available | No US generic as of 2025 | No US generic as of 2025 | | Patient assistance program | AZ&HEART (cardiovascular indication) | NovoCare Patient Assistance Program |

Neither drug is cheap without insurance. Women on Medicaid should check their state formulary: dapagliflozin coverage varies significantly by state, while insulin degludec is more consistently covered because it addresses a life-sustaining need in type 1 diabetes.

The $35 Insulin Cap and What It Means for Tresiba

The Inflation Reduction Act capped Medicare Part D cost-sharing for insulins at $35 per month as of 2023. This cap applies to insulin degludec for Medicare beneficiaries. It does not apply to dapagliflozin, which is not insulin. Women on Medicare who need basal insulin will find Tresiba substantially more affordable than Farxiga at the pharmacy counter if their primary need is glucose control rather than heart failure or CKD protection.

Access Barriers Specific to Women

Prior authorization is common for both drugs. For Farxiga, payers may require proof of a type 2 diabetes diagnosis and failure of metformin before approving it for glucose lowering alone. The heart failure and CKD indications sometimes bypass the diabetes-first requirement. For Tresiba specifically, some plans require a trial of insulin glargine U100 (a lower-cost biosimilar) before approving degludec, because of degludec's premium price relative to glargine.

Women in rural areas face an additional access barrier for Tresiba: proper refrigeration before first use and temperature-stability concerns during travel. Dapagliflozin is an oral tablet with no cold-chain requirement.

Sex-Specific Physiology: How Being a Woman Changes the Pharmacology

Menstrual Cycle and Glucose Variability

Progesterone causes insulin resistance in the luteal phase (days 15 to 28 of a typical cycle). Women using dapagliflozin may notice slightly higher glucose in the luteal phase despite consistent dosing, because SGLT2 inhibition does not fully compensate for progesterone-driven resistance. Women on basal insulin often need luteal-phase dose increases of 10 to 20%, though this is extrapolated from insulin-resistance data rather than a degludec-specific trial.

PCOS: Where Farxiga Has a Distinct Potential Advantage

Women with PCOS have a prevalence of type 2 diabetes roughly 3 to 7 times higher than age-matched controls. The underlying driver is hyperinsulinemia and insulin resistance, not absolute insulin deficiency. Adding more insulin (Tresiba) to a hyperinsulinemic state worsens the hormonal environment. Dapagliflozin, by contrast, reduces circulating glucose without raising insulin levels and produces modest weight loss, both of which may benefit the androgen excess and ovulatory dysfunction in PCOS.

A practical framework for women with PCOS and type 2 diabetes:

• If A1C is <9% and kidney function is preserved (eGFR >45 mL/min/1.73m²): start with metformin, then consider dapagliflozin as a second agent before insulin.
• If A1C is >9% or symptomatic hyperglycemia is present: short-term basal insulin (including degludec) is appropriate to bring glucose down rapidly, with a plan to taper as weight loss and other agents take effect.
• Once A1C reaches target on degludec plus oral agents, shared decision-making about transitioning away from insulin should happen at every visit.

This stepwise approach is consistent with ADA Standards of Care 2024, which recommend GLP-1 receptor agonists or SGLT2 inhibitors before insulin in type 2 diabetes when the primary driver is not severe hyperglycemia.

Perimenopause and Post-Menopause

Estrogen has insulin-sensitizing effects. As estrogen declines during perimenopause, insulin resistance rises, and many women find their previously well-controlled type 2 diabetes deteriorates. Both drugs become more relevant here, but in different ways.

Dapagliflozin's weight-stabilizing and blood-pressure-lowering effects may offset some of the metabolic burden of estrogen withdrawal. The genital mycotic infection risk, however, increases in post-menopausal women because genitourinary syndrome of menopause (GSM) alters the vaginal and vulvar microbiome, making the glucose-rich urinary environment more hospitable to Candida. Women with GSM on SGLT2 inhibitors have higher rates of vulvovaginal candidiasis than pre-menopausal women on the same drug. If you are using vaginal estrogen for GSM alongside Farxiga, discuss this combination with your prescriber.

Insulin requirements generally increase in perimenopause due to rising insulin resistance. Tresiba's stable, peakless profile suits the post-menopausal woman whose glucose variability increases because the cycle-driven insulin-resistance patterns disappear and are replaced by a consistently higher basal resistance.

Female-Pattern Cardiovascular and Kidney Risk

Women develop cardiovascular disease about 10 years later than men on average, but diabetes narrows or eliminates that sex-based protection. A woman with type 2 diabetes has a roughly 44% higher relative risk of fatal coronary heart disease than a man with diabetes of comparable severity. This is precisely why the cardiovascular benefits of dapagliflozin seen in DAPA-HF matter for women. Farxiga is not just a glucose drug. For a post-menopausal woman with type 2 diabetes and stage 3 CKD or established heart failure, the SGLT2 inhibitor belongs in the regimen for reasons that have nothing to do with A1C.

Pregnancy, Lactation, and Contraception: What Every Woman Must Know

Farxiga (Dapagliflozin)

Dapagliflozin is contraindicated during the second and third trimesters of pregnancy based on animal data showing fetal renal toxicity and reduced fetal body weight. Human pregnancy data are limited; most exposures in published case series occurred in the first trimester before the pregnancy was recognized. The FDA prescribing information states that dapagliflozin should be discontinued as soon as pregnancy is detected.

Women of reproductive potential who are sexually active and not planning pregnancy should use reliable contraception while taking dapagliflozin. If you are trying to conceive, discuss stopping dapagliflozin before attempting pregnancy.

Lactation data are also absent for dapagliflozin. Animal studies show transfer into milk. Because of the potential for serious adverse effects in a nursing infant, the prescribing information advises against use during breastfeeding.

Tresiba (Insulin Degludec)

Insulin degludec does not cross the placenta in clinically meaningful amounts. Insulin analogs, including degludec, are used in pregnancy when basal insulin is needed, though insulin detemir has a more established human pregnancy safety profile and is often preferred in guidelines. The ACOG Practice Bulletin on Pregestational Diabetes (2018) does not list degludec as a first-line choice in pregnancy, primarily because the long-term human fetal-safety data are less extensive than for detemir or NPH.

For a woman with type 1 diabetes who becomes pregnant on Tresiba, immediate consultation with a maternal-fetal medicine specialist and endocrinologist is necessary. Switching to detemir or NPH is a common clinical decision but should not be done without specialist guidance, as glycemic control disruption in early pregnancy carries its own fetal risks.

Insulin does not transfer into breast milk in clinically significant quantities, and basal insulin therapy is compatible with breastfeeding.

Trying to Conceive with Type 2 Diabetes

If you have type 2 diabetes and are planning a pregnancy, the general approach endorsed by ACOG is to achieve A1C below 6.5% before conception and to transition to insulin-based therapy, because the human safety data for oral antidiabetic agents in pregnancy remain limited. That means most women will transition off dapagliflozin to insulin before conceiving. Tresiba may then be used in the preconception period as part of a basal-bolus regimen, with a switch to detemir considered once pregnancy is confirmed.

Who This Is Right For (and Who It Is Not)

Farxiga May Be a Better Fit If You

• Have type 2 diabetes with preserved kidney function (eGFR >45 mL/min/1.73m² for the glucose indication; eGFR >25 mL/min/1.73m² for the CKD indication)
• Also have heart failure (HFrEF or HFpEF) or CKD, where Farxiga has direct FDA-approved organ-protective benefits
• Are overweight or obese and benefit from the modest weight loss associated with SGLT2 inhibition
• Have PCOS with insulin resistance and prefer to avoid adding exogenous insulin
• Are post-menopausal, not breastfeeding, and not planning pregnancy
• Prefer an oral medication over daily injections

Farxiga Is Not Appropriate If You

• Have type 1 diabetes (off-label use only; risk of euglycemic DKA is real and under-recognized)
• Have eGFR <25 mL/min/1.73m² for the glucose-lowering indication (the drug simply does not work well enough at low kidney function to lower glucose)
• Are pregnant or breastfeeding
• Have a history of recurrent genital yeast infections or urinary tract infections
• Have had a lower-limb amputation (FDA carries a warning for increased amputation risk with this drug class based on CANVAS trial data, though DAPA-HF and DECLARE-TIMI 58 did not replicate this signal)

Tresiba Is a Better Fit If You

• Have type 1 diabetes and need exogenous basal insulin to survive
• Have type 2 diabetes with A1C above 9% or symptomatic hyperglycemia requiring rapid correction
• Have experienced nocturnal hypoglycemia on insulin glargine; DEVOTE showed degludec's 53% lower rate of nocturnal hypoglycemia compared to glargine
• Are pregnant and require basal insulin (though a specialist should weigh degludec against detemir)
• Have kidney function too low for SGLT2 inhibitors to lower glucose effectively
• Are on Medicare and benefit from the $35/month insulin cap

Tresiba Is Not Ideal If You

• Are trying to minimize injection burden and oral options remain adequate
• Have severe needle phobia or lack reliable cold-chain storage (pre-first use refrigeration is required)
• Have type 2 diabetes with predominantly insulin resistance rather than insulin deficiency, where adding basal insulin without addressing resistance may cause weight gain and worsen hyperinsulinemia

Switching Between Farxiga and Tresiba: What to Expect

Switching from Farxiga to Tresiba is not a simple substitution. Dapagliflozin lowers glucose by increasing urinary glucose excretion; insulin degludec lowers glucose by moving glucose into cells. The mechanisms do not overlap, and the transition requires glucose monitoring and potentially a temporary gap period during which glucose rises.

If your clinician recommends moving from dapagliflozin to basal insulin, expect to check fasting glucose daily, start with a conservative starting dose of degludec (typically 10 units at bedtime or with the main meal, per ADA titration guidance), and titrate every 3 days based on fasting readings.

Going the other direction, from Tresiba to Farxiga, is feasible only in type 2 diabetes where insulin deficiency is not absolute. Your prescriber will typically taper the insulin dose slowly while the SGLT2 inhibitor is introduced, watching for rebound hyperglycemia. In type 1 diabetes, Tresiba cannot be dropped for Farxiga without exposing you to uncontrolled hyperglycemia and DKA.

The Evidence Gap in Women: What We Do Not Yet Know

Women were underrepresented in both DAPA-HF (23% of participants) and DEVOTE (approximately 37% of participants). Sex-stratified analyses are available but were not powered to detect meaningful differences in primary endpoints by sex. We do not have strong data on how the menstrual cycle, PCOS, pregnancy history, or menopausal status independently modifies the cardiovascular risk reduction seen with dapagliflozin. The field is extrapolating from male-majority trial populations to female patients. This matters especially for women with HFpEF, which affects women disproportionately and where dapagliflozin's approval was more recently granted. The DELIVER trial that supported the HFpEF indication enrolled a higher proportion of women than DAPA-HF, which is a step forward, but sex-specific subgroup data from DELIVER have not been fully published in disaggregated form as of this writing.