Nasdaq told the company that its shares have failed to meet a minimum $1 per share closing price for 30 consecutive days and may face delisting action.
Other big gainers last month included Accelerate Diagnostics and Natera, and share prices of 23 of the 27 companies in the index increased month over month.
The firm, which markets a clinical immunosequencing assay for leukemia and multiple myeloma, had originally expected to sell its shares at $15 to $17 apiece.
The company, which also trades on the Australian Securities Exchange, has 45 days to submit a plan to the Nasdaq as to regaining compliance.
Overall, the share prices for 18 of the index's 27 companies fell month over month. Exact Sciences was the only firm whose share price improved in the double digits.
The cancer diagnostics developer said it was undertaking the reverse stock split in order to meet the Nasdaq's $1 minimum bid price requirement.
Last month, the company announced two transactions that it said would enable it to regain compliance with the Nasdaq's listing requirement.
An analyst said the DetermaVu test could potentially be best in class for lung cancer diagnosis and that CMS could begin reimbursing for it in late 2020.
The 360Dx Index was up 12 percent last month as shares of Accelerate Diagnostics, Veracyte, and Exact Sciences each improved more than 40 percent month over month.
The firm plans to offer more than 13 million shares of its common stock at $.225 per share. The offering will close on or about Jan. 14.