SIGA Technologies Inc (SIGA)

SIGA Technologies is a small biotech company that makes antiviral drugs. Its most famous drug is called Tecovirimat, sold under the brand name TPOXX. It treats smallpox — a disease that killed millions of people and is now eradicated in nature, but still poses a theoretical risk as a bioweapon. The US government sees SIGA’s drug as insurance against that risk and has been its biggest customer for decades.

SIGA’s story is about a bold bet on a disease that doesn’t exist anymore. The company placed everything on the idea that governments would pay to have a smallpox cure on the shelf, just in case. That bet shaped the company’s entire business model and, for better and worse, made it completely dependent on government demand.

How SIGA got to smallpox

SIGA Technologies was started in 1981 as a biotech startup focused on antivirals — drugs that fight viral infections. For most of the 1980s and 1990s, the company worked on various viruses without major success. Then came a critical turning point. After the September 2001 attacks in the United States, national security experts became worried that smallpox could be weaponized by terrorists. Smallpox was declared eradicated in 1980, and vaccination had stopped decades earlier. Most Americans had no immunity. The idea of a smallpox outbreak terrified the government.

SIGA saw an opportunity. The company already had a small antiviral program. The company decided to focus all its energy on smallpox. It started testing a drug called ST-246, which later became Tecovirimat. This decision to bet the entire company on smallpox — a disease that didn’t exist in the wild and might never return — was either inspired or reckless. In reality, it was both. It saved the company. It also made the company hostage to the government’s fear of bioterrorism.

The long path to approval

Getting a smallpox drug approved is not straightforward. You cannot test it on people who have smallpox, because smallpox exists only in government laboratories now. So SIGA had to test the drug on animals and in laboratory studies of the virus itself. The FDA eventually approved Tecovirimat in 2018 based on animal data and laboratory efficacy. The approval was conditional: the drug had never been used to treat a human smallpox infection, and probably never will be.

The approval meant the drug was legal to use in an emergency. It also meant the government could buy it and store it. The Strategic National Stockpile — the US government’s emergency supply of medicines and medical equipment — became SIGA’s main customer.

The government contract: revenue and risk

Once Tecovirimat was approved, SIGA’s primary business became selling to the US government. The Department of Defense and the Biomedical Advanced Research and Development Authority (BARDA) signed multiyear contracts to purchase the drug and keep it in storage. These contracts provided steady, predictable revenue. From 2018 onward, government purchases became the vast majority of SIGA’s sales.

This arrangement solved SIGA’s survival problem. The company had spent decades developing a drug with a tiny potential market. Now the government was willing to pay for it. SIGA became profitable and profitable in a way that made sense: it was being paid for a precaution, not for actual disease treatment.

The risk is obvious: SIGA is almost entirely dependent on US government decisions to continue buying and storing Tecovirimat. If a future administration decided the bioterrorism threat was overblown, or if a new treatment was developed, or if the government’s budget priorities shifted, SIGA’s revenue could collapse. The company is too small and too narrowly focused on one drug to survive a loss of government demand.

The miniature commercial market

SIGA has tried to develop a civilian market for Tecovirimat. Some countries have purchased small amounts. Some hospitals hold stockpiles. But the global commercial market is tiny. You cannot build a major pharmaceutical company on a disease that does not exist. Most cancer drugs, heart drugs, and antibiotics have millions of potential patients. Tecovirimat has zero. In theory.

This creates a paradox: SIGA is a public company trading on the NASDAQ, so it must answer to shareholders and maintain a stock price. But its business is based on a contingency that may never materialize. The stock price is therefore a pure bet on two things: whether the government keeps buying, and whether the market is willing to pay a premium for the “insurance policy” SIGA represents.

The research challenge and the leverage

SIGA has a small team of scientists and engineers. The company has been trying to develop other antivirals for other rare viruses — monkeypox, for instance — to diversify away from smallpox. Some of these programs showed promise. But the company’s capital and attention are always pulled back toward Tecovirimat and the government contracts that fund it. Biotech is an expensive business. Drug development takes years and billions of dollars. SIGA is small. The company cannot afford the burn rate of large research programs that may not pan out.

This is the structural constraint that shapes SIGA’s strategy: be excellent at the smallpox drug, stay close to government customers, and gradually diversify where possible without risking the core business.

What matters for investors

SIGA’s financial reports are heavily shaped by government contract procurement. Watch for big government orders and multiyear contract extensions. These are announced in press releases and SEC filings (Form 8-K). The company’s annual 10-K filing (SEC CIK 0001010086) will show what percentage of revenue comes from the US government (it is extremely high). Monkeypox, the virus that caused outbreaks in 2022–2023, briefly created hope for a second indication for Tecovirimat, but that opportunity proved limited. For a small biotech company with a single main revenue source, diversification risk is always the key question: will SIGA ever move beyond being a smallpox treatment company? The answer will determine the company’s long-term value.