Biotech stocks have a way of making smart people do dumb things. It starts innocently enough.
You read about a “breakthrough” that sounds like it came straight out of science fiction. A tiny company with a tiny market cap is working on a therapy that could change the standard of care.
You picture the chart before you even open it. A little line. Then a rocket ship.
You buy a starter position because you do not want to miss it, and you tell yourself you will add later if the story keeps getting better.
And then biotech does what biotech always does. It reminds you that in this corner of the market, the business is not the product. The business is the trial.
That one sentence explains most of the pain, and most of the opportunity, in biotech investing. In a normal company, you can look at customers, margins, competitive advantages, and a hundred small indicators that confirm whether management is executing. In biotech, the “indicator” is often a binary event wrapped in statistics, regulatory judgment, and biology’s cruel sense of humor. One press release can erase 50% of your capital before lunch. That is not an exaggeration. It is the admission ticket.
Clinical risk is the obvious danger. You are betting on biology, and biology is not a spreadsheet. A drug can look promising in early studies and fall apart in larger trials. It can work on a surrogate endpoint and fail to deliver real-world benefit. It can show promise in one subgroup and disappoint everywhere else. Sometimes the safety profile is what kills the program, not the efficacy. Most investors treat these setbacks like surprises. They are not. In biotech, failure is the default and success is the outlier.
Regulatory risk is clinical risk with an extra layer of uncertainty. The FDA is not just counting p-values. It is deciding whether the benefit is meaningful enough to justify the risk in real patients. The agency can ask for more data, challenge trial design, narrow a label, or stretch the timeline. Even a “win” can come with enough restrictions and requirements to change the economics of the opportunity. In biotech, time is not just money. Time is dilution.
And that leads to the risk that quietly destroys more returns than bad trial results, the capital structure. Many biotech companies are not traditional businesses. They are research engines funded by the capital markets. They burn cash, often predictably, and they refill the tank by selling stock. When markets are friendly, dilution feels painless. When the market turns, dilution becomes a slow bleed that turns a good scientific story into a bad investment. You can be right about the drug and still lose money because you were wrong about the financing.
Then there is the information environment, which is a polite way of saying biotech is a narrative factory. The science is complex, the milestones are technical, and the incentives are obvious. Management wants to keep the story alive. Analysts want access. Retail investors want hope. Social media wants certainty. Somewhere in the middle is the truth, which is usually probabilistic, nuanced, and boring, which is exactly why it gets ignored.
That is the trap. Biotech can look like investing when it is really event gambling dressed up in lab coats. Investors stop asking what a company is worth and start asking what happens if the trial hits. The catalyst calendar becomes the business plan. That is not investing. That is a coin flip with a press release.
Even after approval, commercial risk is real. Launching drugs is hard. Payers negotiate. Formularies restrict. Doctors move cautiously. Competitors respond. Manufacturing can become a bottleneck. The addressable market can be smaller than investors expected. Pricing can disappoint. Plenty of biotech “winners” in the lab become mediocre businesses in the real world.
So, why do rational investors bother?
Because biotech offers something rare, the possibility of truly massive returns. Not because of multiple expansion. Not because of financial engineering. But because sometimes the science actually works. Sometimes a small company brings a therapy to market that changes outcomes, expands into multiple indications, and becomes a platform. When that happens, the value creation can be extraordinary. You can see 5-baggers and 10-baggers, and occasionally more. That is the honest lure of biotech. The gap between what a company is today and what it could become tomorrow can be enormous.
The problem is that most investors chase the upside in the worst possible way. They buy the story at the top of the hype cycle and hope the calendar saves them.
I prefer signals that are harder to fake.
In a market where individuals are forced to handicap biology, statistics, and regulators, I will gladly take evidence that people closest to the science are putting real money at risk.
Start with insider buying. In biotech, insiders may not know the outcome of a blinded study, and they are restricted around material events, but they know far more than you and I do about the real state of the company. They know trial design. They know what the regulator is pushing back on. They know the competitive landscape. They know the financing needs. They know whether the company is scrambling behind the scenes.
That is why I care about cash buys. Not options. Not stock grants. Cash buys.
The first thing to watch is size and intent. A token purchase makes a nice headline and does not change anything. I want to see an amount that would sting if it goes wrong. The next thing is clustering. One insider buying is interesting. Several insiders buying around the same time is a signal. A CEO, CFO, and director all stepping in is rarely random. It does not guarantee a win, but it tells you confidence is spreading among people with visibility into the real situation.
Here are 3 promising biotech companies with recent insider buying:
Summit Therapeutics (NASDAQ:SMMT) is a cancer-drug company, and the easiest way to understand what they are trying to do is to think of their lead drug as a 2-in-1 approach. One part is designed to help the immune system recognize and attack cancer cells more effectively. The other part is designed to make it harder for tumors to feed themselves by disrupting the blood-vessel support that helps tumors grow and spread. It is not chemotherapy in the old-fashioned sense. It is a targeted antibody drug, more like a guided weapon designed to hit specific biological targets.
That kind of approach is why the upside can be very large. If a cancer drug works in large late-stage studies, it can become a major product. But it is also why the stock can be so violent. Expectations swing. Data is debated. Competitors matter. And the market has no patience when a high-profile result does not match the hype. Insider buying in a name like Summit is worth noting because this is the type of stock that can get punished hard on sentiment alone. When insiders step in after volatility, it often suggests they believe the market is discounting the potential too aggressively. Still, the real driver is simple. The drug has to deliver.
Annexon (NASDAQ:ANNX) is a very different story. This is not cancer. It is the brain and nervous system, which is both the most exciting and the most unforgiving arena in drug development. Annexon’s focus is on calming down an overactive part of the immune system that may be contributing to damage in certain neurological and eye diseases. One way to think about it is this. In some conditions, the immune system is not just fighting threats. It is also creating collateral damage, including harm to healthy connections between brain cells. Annexon is trying to reduce that damage by blocking a specific trigger in the immune pathway.
Their main programs are antibody drugs. One is aimed at neurological disease and would be given through an IV. Another is aimed at certain eye diseases and is delivered locally as an injection into the eye, which sounds intense, but is a common method in ophthalmology. What makes Annexon compelling is also what makes it risky. Neurology trials take a long time, results can be messy, and plenty of smart scientists have been wrong in this field. But when a brain-related therapy truly works, the payoff can be enormous because patients and doctors have so few good options. Insider buying here can be meaningful because it signals confidence in a long, slow process that often tests investors’ patience.
CervoMed (NASDAQ:CRVO) brings us back to the brain, but with a different kind of drug. CervoMed is working on a pill for a type of dementia called dementia with Lewy bodies. This condition can severely affect thinking, memory, and daily functioning, and there are limited effective treatments. Their drug is a small molecule, meaning it is a traditional pill rather than an antibody given by infusion. The advantage is straightforward. If a pill works, it is easier for patients to take, usually easier to manufacture at scale, and often easier to distribute widely.
The opportunity is obvious. Dementia is a huge unmet need, and any therapy that shows meaningful benefit can attract serious interest. The risk is just as obvious. Brain diseases are difficult. Trial endpoints are challenging. “Almost works” is the same as “does not work” when regulators and doctors are making decisions. Insider buying is a confidence signal, but it does not eliminate the basic reality that this is a development stage company where timelines, trial design, and funding matter as much as the science.
That is the big lesson for individual investors. Insider buying in biotech is not a green light. It is a research prompt. It tells you, “This might be worth a closer look,” not, “This will go up.”
Biotech stocks can move 200% on success and fall 60% on disappointment, sometimes overnight. So if you want to participate in the upside, you need rules that protect you from the downside.
The first rule is position size. If one biotech stock can wreck your year, you sized it wrong. These are not the places for oversized bets based on excitement.
The second rule is cash runway. Biotech companies spend money for years before they make any. When cash runs low, they often raise money by selling new shares, which dilutes existing investors. In plain terms, even if the story is good, you can still lose if the company has to issue a lot of stock at a bad price. Always know how long the company can operate before it needs to raise money again.
If you respect those 2 rules, insider buying becomes a useful tool. It helps you avoid chasing hype and instead focus on situations where the people closest to the company believe the market is mispricing the opportunity.
In biotech, hope is everywhere. The edge comes from process, discipline, and knowing when a signal is just a signal, and when it is worth turning into a position.
