Healthcare · Pharmaceuticals
rNPV: Valuing Drug Pipelines
Risk-adjusted NPV for drug pipelines: cash flows weighted by probability of success, an 8.5% WACC, and a worked Phase III asset valued at $1,621M.
Selborne Research · Pharmaceuticals coverage: 7 guides, 6 company profiles, a primer and Excel model
Educational analysis for professional use. This guide is not investment advice or a recommendation to buy or sell any security, and it is not personalised.
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Clinical Risk Belongs in PoS, Not the Discount Rate
Pipeline valuations go wrong in two ways: they ignore clinical failure (plain NPV), or they punish the same risk twice (a sky-high WACC on top of a low probability of success). The standard method (Chandra & Mazumdar, 2024) discounts at a normal cost of capital and applies the probability of success (PoS) at each phase to revenues and remaining R&D. That is risk-adjusted NPV, or rNPV.
rNPV covers drugs still in clinical trials. Marketed drugs need a forecast of the sales they lose when patents expire. The two sum to equity value.
The rNPV Mechanics
For each pipeline asset:
- Forecast commercial cash flows from launch until exclusivity ends: revenue ramp, margin, and tax if modelling after tax.
- Discount at WACC. The worked example uses 8.5% nominal, a 4.50% 10-year Treasury rate plus about four points of equity risk, the rate the pharma model applies to a diversified large drugmaker.
- Multiply by cumulative PoS from the asset’s current phase to approval, using the BIO/Informa table (2011–2020 cohort) or, where the disease area is known, the therapeutic-area rates.
- Subtract remaining development costs, each phase weighted by the probability of reaching it.
Do not raise WACC to 20%+ to “reflect biotech risk”. That double-counts the risk already in the PoS and breaks comparability with the DCF on the same company’s marketed drugs.
Phase III PoS Inputs (BIO 2011–2020)
An asset that passes Phase III is filed with the FDA as a New Drug Application (NDA).
| Transition | Success rate |
|---|---|
| Phase III → NDA | 57.8% |
| NDA → approval | 90.6% |
| Combined Phase III → approval | 52.4% (57.8% × 90.6%) |
From Phase I the cumulative likelihood of approval is 7.9% across all drug types (9.1% for biologics, 5.7% for small-molecule new molecular entities). A Phase III asset has passed most of the gates, so the worked example uses 52.4%.
Worked Example: Phase III Oncology Asset
Illustrative teaching asset inputs:
| Parameter | Value |
|---|---|
| Starting phase | Phase III |
| Launch | Year 3 |
| Peak sales | $2,000M (linear ramp years 3–5, flat through exclusivity) |
| Exclusivity | 10 years from launch (through year 13) |
| Commercial margin | 30% of revenue |
| WACC | 8.5% |
| PoS (Phase III → approval) | 52.4% |
Revenue schedule and discounted cash flows:
| Year | Revenue ($M) | CF at 30% ($M) | PV @ 8.5% ($M) |
|---|---|---|---|
| 0–2 | $0 | $0 | $0 |
| 3 | $667 | $200 | $157 |
| 4 | $1,333 | $400 | $289 |
| 5 | $2,000 | $600 | $399 |
| 6–13 | $2,000 | $600 | $368 → $208 (declining) |
Valuation:
| Step | Result |
|---|---|
| PV of commercial cash flows | $3,094M |
| × PoS 52.4% | $1,621M rNPV |
The unadjusted $3,094M is the asset’s value if approval were certain; at a 52.4% PoS it is $1,621M. The remaining Phase III spend is left out to keep the arithmetic visible. In practice it is deducted in full, because it is paid whatever the trial shows (the PoS guide works through this). The result is one line in a sum-of-the-parts model, beside the DCFs of marketed drugs.
Peak sales and PoS move rNPV more than ±50 bps on WACC does, so stress the clinical assumptions before fine-tuning the discount rate.
rNPV vs Licensing Deals and vs Multiples
Licensing deals, paid as an upfront sum plus payments at each phase (milestones), are comparators only. Convert each one to an implied rNPV with the same PoS table and WACC, so an in-house asset and an external licence are measured on one basis.
Sector multiples cross-check companies that earn mostly from marketed drugs. Damodaran’s January 2026 figures for US Drugs (Pharmaceutical): forward P/E 24.19×, expected five-year EPS growth 17.81%, PEG 1.40, price/sales ~5.6×. These averages drift with the market, and they cannot value Phase II and III assets that do not yet earn anything.
Where rNPV Meets Filings
Large drugmakers run wide pipelines beside concentrated franchises:
- Eli Lilly (FY2025 revenue $65,179M) spends 20.5% of sales on R&D while tirzepatide, its diabetes and weight-loss drug, earns 56.0% of them. In a Lilly model, pipeline rNPV offsets future loss of exclusivity (LOE) on older products (~20.6% of revenue near term). See the Eli Lilly profile.
- Merck has 48.7% of sales in the cancer drug Keytruda, which loses patent protection from December 2028. Its pipeline rNPV lines ask whether new cancer drugs can replace $31,680M of Keytruda revenue. See Merck.
Build the DCF of marketed drugs with each product’s LOE decline, add pipeline rNPV asset by asset, then add net cash to reach equity value. When a result looks wrong, check the PoS inputs before the WACC.
A base business, a drug at its patent cliff, a growing biologic and a Phase III asset, each valued year by year and summed to value per share.
- 15 sections, the patent ladder to a year-by-year sum-of-parts valuation and concentration screens
- 39 pages
- a small molecule at its cliff, a biologic growth driver and a pipeline asset weighted by its phase, plus a base business
- 3 drug schedules
- large-cap innovators on filed product concentration and loss-of-exclusivity dates
- 6-company screen
The Excel model is the primer's sum-of-parts valuation live across 13 sheets: a base-business DCF at an 8.5% WACC; three drug schedules, each set to marketed or pipeline and to a clinical phase that sets its odds; loss-of-exclusivity cliffs that settle on a generic floor; a calendar-year input that turns a filed patent date into a schedule year; the consolidated bridge to value per share; and patent-cliff, concentration and sensitivity views. Change a drug's LOE year, phase or peak sales, or the WACC, and the value moves.
See what's in the Pharmaceuticals Sector Primer →£25 PDF · £59 with the Excel model · £159 for all three Healthcare industries
Frequently Asked Questions
- What is rNPV in drug pipeline valuation?
- Risk-adjusted net present value (rNPV) forecasts commercial cash flows for a development asset, multiplies revenues and costs by cumulative probability of success (PoS) at each phase, and discounts at a normal weighted average cost of capital. Clinical risk sits in the PoS haircuts, not in an inflated hurdle rate.
- What discount rate should pharma analysts use for rNPV?
- Practitioner convention uses a normal corporate WACC for commercial-stage and pipeline cash flows. The pharma model uses 8.5% nominal for a diversified large-cap drugmaker: a 4.50% 10-year U.S. Treasury rate plus about four points of equity risk. PoS by phase carries clinical risk; bumping WACC to 25–30% double-counts it.
- How do you calculate rNPV for a Phase III asset?
- Forecast revenue from launch through exclusivity, apply commercial margin to get cash flow, discount each year at WACC to get present value, then multiply by cumulative PoS from the current phase to approval. For an asset starting Phase III, BIO 2011–2020 data imply 57.8% from Phase III to a New Drug Application (NDA, the filing that asks the FDA to approve) and 90.6% from NDA to approval, or 52.4% combined.
- When should you use rNPV instead of P/E?
- P/E and PEG work for profitable, commercial-stage pharma. Pre-revenue biotech and material pipeline optionality require EV/Revenue, EV/R&D, or asset-level rNPV. Sum-of-the-parts models add a DCF of marketed drugs (with each drug's sales loss at patent expiry modelled) to pipeline rNPV lines.
Read next
Drug Development Probability of Success
How probability of success enters a drug valuation: the chain from the current phase, why committed trial spend is not weighted, and biologics vs small molecules.
Patent Cliffs and LOE Erosion
How loss-of-exclusivity erodes branded drug revenue: generic unit-share curves, net-price erosion by competitor count, biosimilar contrast via Humira, and a worked fade on a $3,000M brand.
Pharma R&D Intensity by Company
R&D as a share of revenue at six large drugmakers: where acquired R&D and write-downs are booked, what the PhRMA industry average covers, and why spend is not output.
rNPV for Clinical-Stage Biotech
Single-asset rNPV for clinical biotech: PoS-weighted cash flows at 10.0–10.5% discount, a Phase II worked example at 15.1% PoS, equity equals rNPV plus net cash.
See it applied
These company profiles apply the concepts from this guide to real public companies.