For most of 2019, Cara Therapeutics (CARA -8.53%) and Intellia Therapeutics (NTLA -0.16%) claimed very similar market caps. The two biotechs repeatedly swapped positions for the larger market cap. But thanks to encouraging phase 3 results for its lead drug, Korsuva, Cara is now valued at nearly $150 million more than Intellia.

Market caps don't matter much when it comes to picking the better stock to own over the long run, though. Which of these two biotechs has stronger prospects? Here's how Cara and Intellia compare against each other.

Three people in lab coats in a lab.

Image source: Getty Images.

The case for Cara Therapeutics

Cara Therapeutics doesn't have a product on the market yet, but it's getting pretty close to potentially reaching that milestone. The company announced results on May 29 from the Kalm-1 phase 3 study evaluating Korsuva injection in treating hemodialysis patients with moderate-to-severe chronic kidney disease-associated pruritus (CKD-aP). And those results looked great.

Korsuva blew away the primary endpoint of the study -- statistically significant improvement in itching for patients on a numerical rating scale (NRS) measuring worst itching levels. The kappa opioid receptor (KOR) agonist also proved to be well-tolerated by patients through 12 weeks of treatment.

Cara now awaits the results of another late-stage study evaluating Korsuva injection in CKD-aP patients on hemodialysis. Those results are expected to be announced later in 2019. If they're as positive as the Kalm-1 results, Cara should move forward quickly with filing for FDA approval of its lead candidate.

The biotech already has a big partner lined up to market Korsuva, assuming it wins approval. A joint venture started by Fresenius Medical Care and Vifor Pharma Group will market the drug outside of the U.S., Japan, and South Korea. In addition, Fresenius is going to promote Korsuva in its U.S. dialysis centers.

Cara could have even bigger opportunities. The company should report results later this year from a phase 2 clinical study evaluating an oral version of Korsuva in treating CKD-aP patients who aren't on dialysis. It's also starting phase 2 studies of oral Korsuva in treating atopic dermatitis and chronic liver disease-associated pruritis (CLD-aP).

The case for Intellia Therapeutics

Intellia Therapeutics focuses on developing CRISPR gene editing therapies. The biotech has attracted the interest of two large partners, Novartis and Regeneron.

It's still really early for Intellia's gene editing program. The company doesn't expect to file for the FDA's blessing to begin its first clinical study of lead candidate NTLA-2001 until next year. That program will use CRISPR/Cas9 to target treatment of rare genetic disease transthyretin amyloidosis (ATTR).

Preclinical studies of NTLA-2001 in ATTR were promising. The therapy reduced the circulating TTR protein, which builds up deposits and causes ATTR, by an average of more than 95% in nonhuman primates. Regeneron is collaborating with Intellia on the development of NTLA-2001.

Intellia also expects to pick a candidate by the end of 2019 for targeting acute myeloid leukemia (AML). The biotech is using CRISPR gene editing to modify immune cells in the blood known as T cells so that they'll attack leukemic blasts that express Wilms' tumor 1 (WT1) epitopes (the part of the cancer cells that can bind to an antibody).

In addition, Intellia has made progress in preclinical testing of a gene editing therapy targeting the treatment of hemophilia B. This is another program with which the company is partnering with Regeneron.

Better buy

There's certainly a pretty good argument to make that Intellia could have more far-reaching therapies over the long run. That's why the biotech claims a market cap of more than $650 million even though it's years away from even the possibility of having an approved drug on the market.

However, Cara Therapeutics appears to be the better choice right now, in my opinion. The company should have a great chance at winning FDA approval for Korsuva injection in treating CKD-aP patients on hemodialysis. And if oral Korsuva proves to be effective as well, Cara will be worth a lot more than it is today. There are still risks for this biotech stock, but I think that Cara ranks as one of the more attractive small-cap stocks on the market right now.