Grifols reported first-half 2026 results on July 28, and the number that carried the release was a 12.8% jump in immunoglobulin sales at constant currency, a franchise that has anchored the Spanish plasma company’s business for years and again outpaced the group as a whole. Armistice Capital holds a position in the stock, which trades on Nasdaq as an American depositary receipt under the ticker GRFS.

Immunoglobulins Outpace the Rest of the Business

Total revenue for the six months through June reached €3.57 billion, up 2.6% at constant currency. Biopharma, the division that houses immunoglobulins and other plasma-derived proteins, grew 5.4%. Within it, intravenous immunoglobulin rose 12.5% and subcutaneous formulations rose 17.7%, for a combined immunoglobulin gain of 12.8%.

The gap between that growth rate and the group’s 2.6% headline shows up further down the income statement. Adjusted EBITDA reached €854 million, a 23.9% margin, and net profit climbed 28.7% to €227 million. Free cash flow before mergers and acquisitions turned positive at €91 million. The same period last year had produced a €12 million outflow.

Two products account for most of the immunoglobulin gain. Gamunex, Grifols’ long-established intravenous therapy, remains the volume driver. Yimmugo, a newer 10% liquid intravenous immunoglobulin developed and manufactured by Grifols subsidiary Biotest at its production facility in Dreieich, Germany, launched in the United States on Oct. 9, 2025, with Kedrion Inc. distributing it domestically. Both compete in a market where demand has outrun supply for years. Plasma collection volume and fractionation capacity remain the binding constraint on how fast any manufacturer can grow.

That imbalance is structural rather than cyclical. The global immunoglobulin market was valued at $22.15 billion in 2025 and is projected to reach $43.68 billion by 2034, a compound annual growth rate of 7.53%, driven in large part by rising diagnosis of primary immunodeficiency disorders, which affect an estimated 1% to 2% of the U.S. population. Manufacturers have responded by expanding fractionation capacity across the industry, but new plasma centers and production lines take years to bring online, which is why incumbents with established collection networks, Grifols among them, have captured much of the growth so far.

Diagnostics Extends the Same Plasma Infrastructure

Grifols’ diagnostics business draws on the same donor-screening operations that feed its plasma collection, and it delivered its own milestone in April, when the FDA approved the company’s Procleix Plasmodium Assay. The test runs on the Procleix Panther System and detects ribosomal RNA from the five parasite species that cause human malaria: P. falciparum, P. knowlesi, P. malariae, P. ovale and P. vivax.

Blood centers had previously relied on travel-history questionnaires to defer donors who might carry malaria, a method that sidelines otherwise-eligible donors regardless of whether they were actually infected. Molecular screening lets centers test the donation instead.

“We are excited to announce the FDA approval of an additional Procleix blood screening assay, demonstrating Grifols’ continued commitment to transfusion safety,” Antonio Martínez, president of Grifols Diagnostic, said in a statement.

A Balance Sheet Rebuilt Under Scrutiny

Grifols has spent much of the past two and a half years working to restore investor confidence after Gotham City Research accused the company in January 2024 of overstating earnings and understating debt, allegations the company has disputed. The stock has still lost roughly a quarter of its value since those claims surfaced, and it now trades around $7.72, well below its 52-week high of $10.23.

Against that backdrop, the first-half numbers matter as much for the balance sheet as for the income statement. Net leverage stood at 4.2 times at midyear, down from 4.6 times at the end of 2024, and the company has said it is targeting 3.5 times by 2027. Grifols refinanced its 2027 debt maturities during the first half and redeemed €500 million of bonds due in 2030. Its next major repayment obligation is now 2028. Management pointed to the swing in free cash flow as evidence the deleveraging plan is on schedule and reiterated full-year 2026 guidance, which calls for adjusted EBITDA growth of 5% to 9% at constant currency and a margin floor of 25%.

That guidance omits a specific revenue target, a departure from prior years that drew a warning from Barclays when it was first disclosed alongside 2025 full-year results, on the grounds that the omission could revive the governance questions that followed the Gotham City Research report. Grifols’ 2025 revenue came in at €7.52 billion, up 7% on a reported basis. Whether the market treats the absence of a 2026 revenue figure as routine or as a signal worth parsing further will likely depend on how the second half plays out.

A Faster Growth Rate Than the Market Leader

CSL Behring, the plasma division of Australia’s CSL Limited, is the largest immunoglobulin producer. Its Privigen and Hizentra brands generated a combined $6.2 billion in the fiscal year ended June 2026. Revenue was roughly flat for the full year, weighed down by Medicare Part D changes and channel inventory normalization in the first half, then recovered to 7% growth in the second half once those headwinds cleared.

CSL management has guided to mid-to-high single-digit immunoglobulin growth going forward, describing that pace as roughly in line with the broader market. Grifols’ 12.8% growth over the same broad window sits well above that range, though the two companies report on different fiscal calendars and cannot be compared quarter for quarter. The gap illustrates why a demand-outstripping-supply market benefits manufacturers unevenly: newer capacity, a fresh product launch in Yimmugo and a smaller revenue base all make a faster growth rate easier to post than for an incumbent the size of CSL Behring.

Institutional Ownership Spans the Spectrum

Grifols counts roughly 192 institutional owners across its 13F and NPORT filings, which combined hold about 175 million shares, according to Fintel data. The largest positions belong to Brandes Investment Partners and Capital World Investors, both long-standing holders, alongside more recent entrants such as Janus Henderson and Millennium Management.

Armistice Capital’s position is smaller by comparison. The New York hedge fund, founded by Steven Boyd and run as a global, long/short, value-oriented and event-driven strategy concentrated in healthcare and consumer names, managed roughly $8.17 billion as of its 13F filing for the quarter ended June 30, 2026. Within that portfolio, Grifols is a comparatively small position: the fund reported a new stake of roughly 2.9 million shares, valued near $21 million, equal to about 0.3% of its disclosed holdings. The timing places the position squarely within the same window as the earnings report, though 13F filings disclose holdings only as of quarter-end and do not reveal the reasoning behind a manager’s trade or when within the quarter it was built.

Armistice’s appearance alongside Brandes, Capital World, Janus Henderson and Millennium reflects a broader pattern among healthcare-focused hedge funds this year, several of which have added exposure to plasma-derived therapeutics as a category insulated from some of the biotech sector’s binary regulatory risk. Unlike a single-asset drug approval, immunoglobulin demand is diversified across thousands of prescribers and payers, and the supply constraint that has kept prices firm gives established manufacturers a degree of pricing durability that newer biotech names, dependent on a single trial readout, do not share.

Two analysts covering GRFS currently rate the stock a buy. Their average 12-month price target, $10.87, implies upside of roughly 41% from current levels. Whether that target proves out will hinge less on any single earnings beat than on whether Grifols can sustain the immunoglobulin growth rate through a full product cycle for Yimmugo and keep deleveraging on pace toward its 2027 target.