MDGL vs VKTX: Which Is the Better Buy in 2026?

Same yardstick, side by side (as of September 2026). Valuation lined up like this is most meaningful for two names in the same corner of the market, which these are. Figures are approximate; verify before investing.

The metrics above tell you which is the marginally better business. The bigger risk for most people is not picking the slightly worse stock, it is over-concentrating. MDGL and VKTX share themes, so owning both, or adding either to what you already hold, can quietly push a large share of your portfolio into one bet.

This is the part a generic comparison page cannot answer, because it depends on what you own. Connect your brokerage and Walnut shows your real, combined MDGL and VKTX exposure, flags overlap with your existing positions, and tells you if adding one would tip you past a concentration you are comfortable with, read-only by default, with your login staying at your broker. Walnut is not an investment adviser.

Madrigal Pharmaceuticals (Nasdaq: MDGL) is a commercial-stage biopharmaceutical company built around Rezdiffra (resmetirom), an oral thyroid hormone receptor beta agonist that in March 2024 became the first FDA-approved treatment for MASH with moderate to advanced fibrosis. The company has transitioned from a clinical-stage developer into a revenue-generating commercial operation, with more than 42,250 patients on Rezdiffra as of the first quarter of 2026 and a US sales force focused on liver specialists and the roughly 460,000 diagnosed F2/F3 MASH patients being seen by those doctors.

Full MDGL guide

Viking Therapeutics (VKTX) is a clinical-stage biopharmaceutical company developing novel therapies for metabolic and endocrine disorders. Its highest-profile program is VK2735, a dual GLP-1 and GIP receptor agonist for obesity, being developed in both injectable and oral forms, which puts Viking among the most closely watched challengers in the booming weight-loss drug market dominated by Novo Nordisk and Eli Lilly. Viking is also developing VK2809, a thyroid-hormone receptor beta agonist for non-alcoholic steatohepatitis (NASH/MASH), and VK0214 for a rare disease (X-linked adrenoleukodystrophy). As a clinical-stage company, Viking has no approved products and generates essentially no product revenue, funding itself from cash on its balance sheet. Headquartered in San Diego, California, VKTX is a speculative, binary biotech whose value hinges on clinical-trial outcomes and the eventual commercial path for its lead obesity drug.

Full VKTX guide

Both fit overlapping themes, but they are not interchangeable. The useful comparison is which set of drivers and risks you want exposure to.

• MDGL drivers: Rezdiffra revenue ramp; MASH market expansion.
• VKTX drivers: Lead obesity program (VK2735); Pipeline breadth in metabolic disease.

A faster-growing, richer-valued name usually swings harder, so it suits a longer horizon and a higher tolerance for volatility; a steadier, more cash-generative business suits a more conservative or income-minded investor. The honest test is which set of risks you could hold through a drawdown: MDGL is a single-product company, so the entire thesis hinges on Rezdiffra, and any slowdown in patient adds, reimbursement pressure or safety signal would hit hard. For VKTX, viking is a clinical-stage biotech with no approved products and essentially no product revenue, so it is highly speculative and potentially binary.

Growth-minded investors who believe the theme has years to run tend to accept the richer multiple for more upside; value-minded investors lean toward the cheaper forward earnings and steadier profile. Pick MDGL if you believe its drivers more; VKTX if you believe its. Many investors hold both, but since they share themes, that is a concentrated bet, not diversification. Decide deliberately and check overlap. For the full detail, see the MDGL and VKTX guides.

MDGL. Madrigal is valued as a high-growth commercial biotech, trading around 11 times trailing sales while still reporting quarterly losses as it funds commercialization. The market is pricing in continued rapid revenue growth from Rezdiffra rather than current earnings. Figures are approximate and drawn from first-quarter 2026 reporting.

VKTX. Viking has no earnings to value on a P/E basis; the stock is priced on the probability-weighted potential of its pipeline, above all VK2735 in obesity, and on acquisition speculation. The shares are highly volatile and move sharply on trial readouts and deal rumors. Cash runway matters because additional fundraising could dilute holders. All figures are approximate and should be verified against current filings.

Headline figures (approximate, JULY 2026): MDGL shows revenue (ttm) ~$1.1B, q1 2026 rezdiffra net sales ~$311M (+127% YoY), q1 2026 net loss ~$94M, market cap ~$12B; VKTX shows business stage Clinical-stage biotech, no approved products, lead program VK2735 (dual GLP-1/GIP agonist) for obesity, injectable + oral, other programs VK2809 (NASH/MASH), VK0214 (rare disease), product revenue ~$0 (no approved products).

MDGL and VKTX are related but distinct: same themes, different businesses and risks. Neither wins in the abstract; the right pick is whichever thesis you actually believe, sized so you are not over-concentrated in one theme. Walnut can show your combined MDGL and VKTX exposure against your real portfolio. It is not an investment adviser.