Chimerix’s initial public offering is complete with more than 8.4 million shares in the antivirals developer sold.

That total includes the over-allotment, the additional shares of common stock underwriters were allowed to purchase at the IPO price of $14 per share. Beyond the 7.3 million shares offered in the IPO, underwriters had the option of purchasing more than 1 million shares in the over-allotment.

At $14 per share, Durham-based Chimerix (Nasdaq: CMRX) raised $117.8 million from the offering.

Investors have been receptive of Chimerix’s offering; the company’s stock quickly jumped 34 percent on the day of the IPO and the stock price has mostly stayed above the $18 mark since. On Wednesday Chimerix stock price climbed as high as $19.65 before closing at $18.75.

Chimerix, which does not yet have any commercially-available products, spent $27.8 million on R&D last year, according to filings. With lead compound CMX001 ready for phase III clinical trials this year, Chimerix will shell out even more money on R&D. But the company has more money than it initially expected to raise. Chimerix had said it expected to net $93.2 million from raising $102.5 million from the IPO. Including the over-allotment, Chimerix will net approximately $107.4 million.

An estimated $45 million of the IPO proceeds have been designated for the phase III clinical trials of CMX001, the antiviral being studied as a way to prevent infection in patients who are undergoing stem cell transplants. Remaining proceeds will be spent on working capital.

Although Chimerix isn’t yet selling any drugs, it already has revenue. The company reported $33.7 million in 2012 revenue, split nearly evenly between its partnerships and contracts. The company last year licensed experimental HIV drug CMX157 to partner Merck. Merck paid Chimerix $17.5 million up front for the phase I compound and Chimerix could gain up to $151 million in milestones, depending on CMX157’s progress in clinical trials.

Besides the research on CMX001 in stem cell transplants, the company is also developing that compound as a potential countermeasure against smallpox. That work is being done under a contract from the Biomedical Advanced Research and Development Authority, or BARDA. The contract is valued at up to $81 million, depending on that compound’s progress.

Chimerix expects to start the phase III trials later this year studying CMX001 in stem cell transplants. The compound is on the Food and Drug Administration’s “fast track,” a designation reserved for new drugs that address serious diseases that have few, if any, treatments.