Cyanotech Corp., which produces and sells health products from microalgae, posted a narrower loss in its fiscal fourth quarter after product sales on Amazon increased fourfold from the previous three months.

The Kona-based company said Thursday that its loss in the January-March quarter was $274,000, or 5 cents a share, compared with a loss of $4.1 million, or 73 cents a share, in the year-earlier period.

For the fiscal year that ended March 31, Cyanotech pared its loss to $1.2 million, or 21 cents a share. That compares with a loss of $4.4 million, or 79 cents a share, in the previous year when the company reduced the value of expected future income tax savings by $3.6 million. Sales for fiscal 2017 edged up 0.6 percent to $32 million from $31.8 million.

“While we suffered from high legal costs (an increase of $1.2 million in such fees) this year, our results reflect positive momentum in the areas where we are focused strategically,” President and CEO Gerry Cysewski said in a statement. “Additionally, we instituted production efficiencies and a restructuring that should generate cost savings in the next fiscal year.”

Cysewski said sales of packaged Spirulina Pacific and BioAstin showed modest growth of 2.8 percent and 0.1 percent, respectively, during the fiscal year, with sales to Costco increasing 25 percent.

Cyanotech’s stock fell 5 cents, or 1.5 percent, Thursday to close at $3.35. The results were announced before the stock market opened.