Oral GLP-1s are expanding the obesity market, with no visible impact on new Zepbound prescriptions

Overview

This report is J.P. Morgan's prescription-tracking update on Eli Lilly & Company's obesity treatment business, focusing on the impact of oral GLP-1 launches on the obesity market and on Zepbound. The report argues that oral Wegovy's launch has been solid and is more likely to expand the obesity treatment market—especially among lower-BMI, needle-averse, and price-sensitive patients—rather than directly cannibalize demand for Zepbound.

Core views

The core views are: first, the early ramp of oral Wegovy is positive for the overall obesity drug category; second, Zepbound remains one of the main products driving prescription growth in the obesity market and maintains a high share of new patient starts; third, the success of oral Wegovy provides a positive read-through for LLY's future oral candidate orforglipron; fourth, current IQVIA data has capture gaps, so prescription readings should be interpreted cautiously in conjunction with company disclosures and known data issues.

Analysis framework

The report mainly uses IQVIA prescription data to track TRx, NRx, low-dose NRx, and weekly and quarterly prescription trends, and cross-validates them against data points disclosed by Novo as well as LLY management's comments on fluctuations in data capture. Low-dose NRx is used as a proxy for new Zepbound patient starts.

Methodology notes

• Prescription data trackingTRx and NRx monitoring

  Use total prescriptions and new prescriptions to measure launch ramp and category growth for obesity drugs.

  The report compares weekly prescription changes for oral Wegovy, Foundayo, Zepbound, and the overall obesity market to assess whether oral drugs are expanding the market or crowding out demand for injectables.

• New patient proxy metricLow-dose NRx

  Use Zepbound low-dose NRx as an approximate indicator of new patient starts.

  Over the past four weeks, Zepbound low-dose NRx accounted for about 70% of the injectable market, leading the report to conclude that oral Wegovy has not yet materially affected new patient starts for Zepbound.

• Data quality adjustmentIQVIA undercount warning

  Prescription data has capture issues and needs to be checked against company disclosures.

  There have been undercount issues for Zepbound vial and Kwikpen since the week ending April 24, and data issues for Foundayo since the week ending May 22; Novo's disclosed oral Wegovy prescription figures are also above IQVIA's readings.

Asset mapping & comparison

Structured mapping from thesis to named assets (strengths, weaknesses, peers, risks).

• Eli Lilly & Company / LLY.O

  The covered company; its obesity treatment franchise is the core focus of the report.

  Strengths

  Zepbound is showing strong prescription growth and new patient starts, and orforglipron is positioned to benefit from market education around oral GLP-1s.

  Weaknesses

  Some prescription data has capture gaps, so short-term tracking may understate or distort the true trend.

  Comparison

  Compared with Novo's oral Wegovy, the report views its strong launch performance as a signal of category expansion rather than a negative competitive signal for LLY.

  Risks

  If oral GLP-1s ultimately begin to displace injectable demand, or if Zepbound's share of new patient starts declines, the investment thesis would weaken.

• Zepbound

  LLY's core injectable obesity treatment product.

  Strengths

  The report views it as still best-in-class in tolerability and efficacy, and it contributes most of the incremental prescription growth in the obesity market.

  Weaknesses

  There are IQVIA data undercount issues for vial and Kwikpen, so short-term prescription readings are not fully clear.

  Comparison

  After the launch of oral Wegovy, there are not yet obvious signs that Zepbound new patient starts have been negatively affected.

  Risks

  Future adoption of oral drugs, migration of price-sensitive patients, or changes in reimbursement structure could affect growth.

• orforglipron

  LLY's future oral obesity treatment candidate, for which the report sees oral Wegovy's performance as a positive read-through.

  Strengths

  Validation of demand for oral GLP-1s helps reduce uncertainty around future market acceptance at launch.

  Weaknesses

  The report does not provide the latest clinical or commercialization data for orforglipron itself.

  Comparison

  The steady ramp of oral Wegovy suggests the oral format may unlock underpenetrated patient populations.

  Risks

  Launch timing, efficacy and tolerability, pricing, and interaction with existing injectable products still need to be monitored.

• oral Wegovy

  A comparable oral GLP-1 reference product used to assess market expansion and potential competitive impact.

  Strengths

  Week 23 TRx and NRx performance has been solid, and Novo's data suggests actual demand may be higher than IQVIA's readings.

  Weaknesses

  There are large discrepancies across data sources, so the true prescription scale needs ongoing validation.

  Comparison

  At present it looks more like an expansion of the obesity market than a clear squeeze on Zepbound.

  Risks

  If future growth mainly comes from substitution away from injectables rather than newly added patients, the positive interpretation for LLY would change.

Key data

• Current price of LLY$1,098.57Price date is 2026-06-18.
• Oral Wegovy week 23 TRxabout 161.5kBased on IQVIA data; about 159.4k in the prior week, and Novo data suggests IQVIA may be understating it.
• Oral Wegovy week 23 NRx132.9kAbout 20% of obesity-category NRx.
• Foundayo week 10 TRx21,648Affected by IQVIA data issues; LLY said data capture rates may fluctuate during the launch period.
• Obesity market weekly TRx YoY growthabout 79% / about 499k TRxMeasured over the four weeks through 2026-06-12, with growth driven mainly by Zepbound.
• Zepbound TRx YoY growthabout 59% / about +240k TRx per weekContributed about 48% of the obesity market's YoY TRx growth.
• Zepbound low-dose NRx shareabout 70%Share of the injectable market over the past four weeks, used as a proxy for new patient starts.
• Difference between Novo and IQVIA oral Wegovy TRxabout 225k vs. about 134kFor the week ending 2026-05-29, Novo's disclosed data was above IQVIA's readings.

Impact & implications

For LLY, the report's conclusion is favorable: if oral GLP-1s mainly expand the treated obesity population rather than substitute for Zepbound, LLY can benefit both from continued Zepbound volume growth and from the future launch opportunity for orforglipron. From an investment perspective, prescription data supports the positive narrative underlying the Overweight rating, but it remains necessary to verify whether oral products are truly expanding the market and whether IQVIA undercounting improves.

Risks

• IQVIA has had data capture issues for Zepbound vial and Kwikpen since the week ending 2026-04-24, which may understate true prescriptions.
• Foundayo has had IQVIA data issues since the week ending 2026-05-22, so early-launch TRx should be interpreted cautiously.
• It remains to be verified whether oral GLP-1s will expand the market over the long term rather than replace injectables.
• Prescription data is not the same as revenue, profit, or net price performance, and is still affected by reimbursement, discounts, and channel mix.
• J.P. Morgan discloses potential conflicts of interest with Eli Lilly & Company, including market making, client relationships, investment banking business, and shareholdings.

What to watch

• Whether oral Wegovy's subsequent TRx, NRx, and share of obesity-category NRx continue to rise.
• Whether Zepbound low-dose NRx and its share of new patient starts remain high.
• Whether IQVIA data capture issues for Zepbound vial, Kwikpen, and Foundayo are fixed.
• Whether the gap between Novo's disclosed data and IQVIA's readings narrows.
• orforglipron's launch timing, initial prescription ramp, tolerability, and efficacy feedback.
• Whether the obesity market's four-week YoY prescription growth and quarterly prescription trend continue.