Image source: Getty Images.

Stocks fell on the final trading day of 2016, with a slight decline still leaving the Dow Jones Industrial Average (^DJI 0.06%) up an impressive 13% on the year. The S&P 500 (^GSPC -0.22%) index shed a bit more during the session, and trailed the Dow by posting a 9% annual gain.

Today's stock market

Index

Percentage Change

Point Change

Dow

(0.29%)

(57.18)

S&P 500

(0.46%)

(10.43)

Data source: Yahoo! Finance.

Volatile gold prices ensured that investors in gold-linked exchange-traded funds, particularly leveraged ones like the Direxion Daily Jr Gold Miners Bull 3X ETF (NYSEMKT: JNUG) and the Direxion Daily Gold Miners Bull 3X ETF (NUGT 0.99%), endured double-digit losses.

As for individual stocks, Cabela's (CAB) and Opko Health (OPK -1.60%) stood out by posting greater price declines than the broader market.

Opko Health fails a trial

Opko Health shares slumped 19% after the biotech announced disappointing results for one of its most advanced clinical trials. The human growth hormone injection, coded as hGH-CTP, failed to produce a statistically significant improvement over a placebo pill in its phase 3 study.

Image source: Getty Images.

hGH-CTP treats growth hormone deficiency, and its potential application was large enough that Opko is partnered with drug titan Pfizer to manufacture and commercialize it around the world. The biotech received a non-refundable payment of nearly $300 million for its development, but a second similarly sized payment, along with all the royalties that would accrue based on actual sales, appear unlikely to materialize now that the treatment failed to achieve its targeted result.

Opko isn't giving up on the drug. In a press release, it suggested that the latest clinical trial findings may have been influenced by outside issues. "As a result," the company explained, "Opko is undertaking further review of the study population as promptly as possible."

The company is diversified enough that even a complete loss on hGH-CTP won't destroy its earnings potential. After all, its commercial products include Rayaldee for treatment of secondary hyperparathyroidism and Varubi for side effects from chemotherapy. But investors had hoped that hGH-CTP would join those FDA-approved drugs in producing steady revenue for the biotech and are now resetting their profit expectations.

Cabela's merger worries

Cabela's shares dipped by as much as 8% before settling to a 5% loss on the day following news that its proposed $5.5 billion merger with Bass Pro shops has hit a few snags. The retailer has received a request from the Federal Trade Commission for additional information to judge whether the move might violate antitrust concerns.

Image source: Cabella's.

In an SEC filing, Cabela's was quick to point out that the request doesn't mean that the FTC believes there are any actual competitive concerns. Instead, it simply "reflects a determination by the FTC that it requires additional information to assess the proposed transaction," executives explained.

At a minimum, the request will likely delay the closing of the merger due to the extra paperwork required, but Cabela's management still targets its original timetable of closing the deal sometime in the first half of 2017.

The deal also hit a complication regarding the credit card business that's slated to be sold to Capital One. Capital One recently informed Cabela's that it doesn't expect to receive the required regulatory approvals in time to allow the deal to close by the proposed deadline. The two companies are working on protecting that piece of the transaction, but it's unclear whether they'll be able to craft new terms that will satisfy all the parties involved.