US Biopharma Market Weekly Prescription Report: Tracking Early-Stage Multiple Launches

Overview

This report is a weekly data report on the US biopharma market by Morgan Stanley (part of the 'Charts of note' series), primarily based on IQVIA prescription data for a comprehensive scan of the US drug market. The report covers trends in overall market prescription volume, performance of key new drugs in early launch, biosimilar penetration, as well as detailed charts across multiple therapeutic areas including cardiovascular, diabetes, immunology, neurology, ophthalmology, rare diseases, and vaccines. The report date is June 5, 2026, with data ending through the week ending May 29, 2026.

Core views

At the overall market level, the US drug market's total weekly prescriptions (TRx) grew +1.6% y/y, accelerating from last week's +1.0%, but the rolling 12-week y/y growth remained at a +1.0% moderate level. Extended Unit (EUTRx) grew +1.4% y/y, slightly below TRx growth, indicating little change in prescription duration structure. New drug tracking is the core content of this report. BMY's Cobenfy (schizophrenia, approved in September 2024) had weekly prescriptions of ~2,900, down from last week's 3,350. The report compares its performance with early launches of reference products like Rexulti, Caplyta, and Lybalvi, noting that to achieve the $296 million consensus revenue estimate for 2026, Cobenfy needs to reach 2-5 times the early prescription volume of these reference products, implying an annual prescription demand of ~197,000 (estimated at a net price of ~$1,450). GILD's Yeztugo (lenacapavir, PrEP, approved in June 2025) had weekly total prescriptions (oral + injection) of ~1,280, with injections accounting for ~730. The report suggests that based on 1Q26 prescription capture rate and price estimates, Yeztugo only needs modest prescription growth to achieve the $222 million consensus revenue for 2Q26. More importantly, Yeztugo has achieved 95% payor coverage, with most payors not requiring co-payments and only a few requiring prior authorization or step therapy, indicating payors are aligning with the US Preventive Services Task Force (USPSTF) guidelines. The overall PrEP market is growing strongly (+14% y/y), with Descovy maintaining >45% market share, all supporting optimistic expectations for the PrEP market in 2026 and beyond. VRTX's Journavx (acute pain, approved in January 2025) had weekly prescriptions of ~18,410. Notably, IQVIA did not capture hospital prescriptions, with hospital/retail prescription ratio of approximately 45%/55%. Additionally, the average prescription duration decreased from 14 days to 10-11 days, expected to extend in 2026. The report estimates that under a 50%-70% GTN assumption and 12-day prescription duration, Journavx needs approximately 1.2-2.1 million annual total prescriptions to achieve the $239 million consensus revenue estimate for 2026. JNJ's Icotyde (moderate-to-severe plaque psoriasis, approved in March 2026) had weekly prescriptions of ~230. Although extremely new to market, JNJ disclosed in 1Q26 earnings that approximately 1,500 patients have received prescriptions from over 1,000 unique prescribers. Early dermatologist feedback considers Icotyde an "attractive oral IL-23 option" with potential to expand the treatable patient pool, but sampling friction may temporarily suppress uptake. The report estimates that under a $8,285/month list price and 0-25% GTN assumption, achieving the $288 million consensus revenue for 2026 would require ~35,000-46,000 annual prescriptions. The report also updates tracking of several existing products: ABBV's Skyrizi and Rinvoq, new immunology drug TRx table (Exhibit 75), 1Q26 immunology pricing analysis, and penetration of biosimilars including Actemra, Avastin, Epogen, Herceptin, Humalog, Humira, Lantus, Lucentis, Neulasta, Neupogen, Prolia, Remicade, Rituxan, Stelara, etc. Among these, Stelara biosimilar has Biocon's Yesintek capturing approximately 34% TRx share and AMGN's Wezlana about 12%; for Prolia biosimilar, Sandoz's Jubbonti launched in June 2025 with a recent weekly share of approximately 31%.

Analysis framework

This report adopts a typical sell-side research 'data tracking' methodology, focusing on high-frequency, standardized monitoring of prescription volume (TRx) as a leading indicator to predict drug sales trends and market share changes. At the data level, the report relies entirely on IQVIA's prescription database and clearly distinguishes between TRx (total prescriptions, including refills), NRx (new prescriptions, including refills but excluding duplicate refills), EUTRx (extended units, weighted by prescription duration). The report emphasizes that IQVIA sales data (NSP) reflects only list prices, not net prices, with rebates/discounts not included, therefore the net price realization for branded drugs is approximately 'sales dollar growth minus volume growth'.

Methodology notes

• Industry/Industry Analysis FrameworkSupply-demand framework

  Prescription volume (TRx) as a leading indicator for drug demand

  In the biopharma industry, prescription volume is a more immediate demand signal than sales data. TRx reflects total prescriptions (including refills), NRx reflects new patients starting therapy, while EUTRx eliminates counting differences between 30-day/90-day prescriptions by weighting prescription duration. By tracking these indicators high-frequency, analysts can predict quarterly sales performance in advance.

• Industry/Industry Analysis FrameworkPenetration Rate S Curve

  Tracking the S-curve of prescription volume in early-stage new drug launches

  After a new drug launch, prescription volume typically follows an S-shaped growth curve. The report benchmarks new products like Cobenfy, Yeztugo, Journavx, and Icotyde against historical similar products' launch trajectories to determine their current stage in the S-curve and whether they have potential to reach consensus revenue targets.

• Company Fundamentals & Financial FrameworkFree cash flow analysis

  Gross-to-Net (GTN) adjustments and net price realization estimates

  In US drug pricing, there's a significant difference between list price (WAC) and net price due to rebates and discounts. When analyzing Journavx and Icotyde, the report estimates the required prescription volume to achieve consensus revenue under different GTN discount assumptions (50%-70% or 0-25%), demonstrating in-depth understanding of the drug pricing structure.

• Industry/Industry Analysis FrameworkValue Chain Upstream-Downstream Transmission

  Impact of payor coverage on new drug uptake

  The Yeztugo case shows that 95% payor coverage, low co-pay requirements, and limited prior authorization are key prerequisites for rapid new product uptake. This reflects that in the US drug market, payers—not just patients or physicians—are the critical node determining new drug market penetration.

Key data

• Overall US Market Weekly TRx y/y+1.6%For week ending 5/29, accelerated from +1.0% previous week
• Rolling 4-week TRx y/y+1.3%Moderate overall market growth
• Rolling 12-week TRx y/y+1.0%Average growth over past 12 weeks
• Cobenfy Weekly Prescriptions~2,900Down from ~3,350 previous week; 2026 consensus revenue estimate $296mn
• Cobenfy Implied Annual Prescription Demand~197,000Estimated at net price ~$1,450 to achieve 2026 consensus
• Yeztugo Weekly Total Prescriptions (oral + injection)~1,280Injections ~730; 2Q26 consensus revenue $222mn
• Yeztugo Payor Coverage95%Most require no co-pay, only少数 need prior authorization
• Journavx Weekly Prescriptions~18,410Hospital prescriptions not counted; average prescription duration 10-11 days
• Journavx Implied Annual Total Prescription Demand~1.2-2.1 millionUnder GTN 50%-70%, 12-day prescription duration assumption
• Icotyde Weekly Prescriptions~230Launched ~3 weeks ago; ~1,500 patients, >1,000 prescribers
• Icotyde Implied Annual Prescription Demand~35,000-46,000Under 2026 consensus revenue $288mn assumption
• PrEP Market Growth+14% y/yYeztugo's market showing strong growth
• Descovy Market Share>45%Maintaining stability

Impact & implications

This report provides investors with a high-frequency data snapshot of the US biopharma market, with the key insight being that while overall market growth is moderate (+1.0% y/y rolling 12 weeks), structural opportunities exist in two main themes: new drug launches and biosimilar substitution. For Cobenfy, despite being an important new mechanism drug in schizophrenia, its current prescription volume still has a significant gap to meet the 2026 consensus estimate, requiring continuous observation on whether its prescription ramp-up can accelerate to 2-5 times reference products' levels. Yeztugo, however, shows more optimistic early launch characteristics with 95% payor coverage and favorable reimbursement conditions laying the foundation for rapid scale-up, while the overall PrEP market growth provides a favorable macro environment. Both Journavx and Icotyde are in extremely early launch stages with volatile data, but the former faces challenges with shortened prescription duration, while the latter is affected by sampling friction, potentially resulting in short-term uptake below potential demand. Regarding biosimilars, Stelara and Prolia biosimilars have rapidly gained significant market share (Yesintek 34%, Jubbonti 31%), indicating that the patent cliff effect of mature biologics continues, with original manufacturers facing continuous pricing and share pressure.