Biotech company valuations can be a little weird. Maybe not as weird as some tech companies that trade in information or communication and have no particular product. Nonetheless, as Sean Williams, writing for The Motley Fool notes, "Most biotech stocks aren’t profitable, and many have no products currently on pharmacy shelves. This means biotech valuations tend to be a hodgepodge of investor emotions, future peak sales expectations, and clinical data."

With that in mind, Williams examines four of the cheapest biotech stocks in the world. Cheap, in this case, might be a relevant term or refer to undervalued stocks.

1. Celgene

Located in Summit, NJ, Celgene (CELG) focuses on cancer drugs, and other severe, immune and inflammatory conditions. It has a deep pipeline with more than 300 ongoing clinical trials. They are being evaluated in patients with hematological and solid tumors, including multiple myeloma, myelodysplastic syndromes, chronic lymphocytic leukemia (CLL), non-Hodgkin’s lymphoma (NHL), triple-negative breast cancer and pancreatic cancer.

The key to Celgene is Revlimid, which has been growing sales by 15 to 20 percent per year, and is projected for $8 billion to $8.3 billion in sales this year. And Revlimid only makes up about 60 percent of company revenue. The company also made a deal in late 2015 with generic drug companies that will keep that competition off their backs until the end of January 2026.

"A double-digit growth rate and shrinking P/E give investors every reason to take a closer look at this biotech blue chip," Williams writes.

Celgene stock is currently trading for $119.19.

2. Jazz Pharmaceuticals

Headquartered in Dublin, Ireland, Jazz Pharmaceuticals (JAZZ) has a diverse portfolio and pipeline, focusing on sleep and hematology/oncology. In the U.S., it’s marketed products include Xyrem for narcolepsy, Defitelio and Erwinaze for hematology/oncology, and Prialt, FazaClo and Versacloz for pain and other indications.

It also has a diverse pipeline, even though Xyrem is its foundational drug. Williams writes, "Like Celgene, Jazz is pretty reliant on a single drug for a majority of its sales, but it’s looking to change that. Aside from focusing on building a physician and patient base for Defitelio, a treatment for severe hepatic veno-occlusive disease, which saw sales double in Q1 to $35.9 million from the year prior, Jazz is looking to its pipeline to do the talking."

Jazz Pharmaceuticals stock is currently trading for $152.78.

3. ANI Pharmaceuticals

Based in Baudette, Minnesota, ANI Pharmaceuticals (ANIP) is a specialty pharmaceutical company that develops, manufactures and markets branded and generic drugs. Recent growth has come from its generic business, doubling in sales to $26.6 million.

The branded business showed sales growth of 44 percent from the first quarter of 2016, hitting $8 million. It currently has 76 drugs in its pipeline. "The company’s press release," Williams writes, "points out that 53 of these 76 products were acquired, and 46 of these 53 should be easily commercialized. In other words, a small army of generic drugs could be hitting pharmacy shelves over the next couple of years, and there’s minimal concern of regulatory red tape holding them up."

ANI Pharmaceuticals stock is currently trading for $49.

4. Corcept Therapeutics

Based in Menlo Park, Calif., Corcept Therapeutics (CORT) focuses on severe metabolic diseases and cancer, as well as psychiatric disorders. At the company’s recent first-quarter financial report, it noted quarterly revenue of $27.6 million, up 72 percent from $16.1 million in the first quarter of 2016. Its revenue guidance for 2017 increased to $125 to $135 million.

Since Williams seems to be using "cheap" as a way of saying "undervalued," Corcept appears to be a little more high-risk than the other companies. It’s also a lot lower priced. He writes, "There is a pretty good reason Corcept may be so cheap: It’s wholly reliant on growth from Korlym, a Cushing’s syndrome drug. It has no other approved therapies. During the first quarter, which Corcept reported a little over a week ago, product sales increased by 72 percent year over year to $27.6 million. … By 2020, Wall Street is looking for $209 million in total sales. Corcept has pushed through the initial slow uptake of its lone drug, but peak annual sales could eventually top the $300 million mark."

The big question, Williams points out, is whether the company can expand its portfolio.

Corcept Therapeutics stock is currently trading for $10.12.