| In millions, except per share items | Dec-31-22 | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 | Dec-31-15 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Revenues: | | | | | | | | |
| Clinical treatment programs - US | 0.1 | 0.1 | 0.2 | 0.1 | 0.4 | 0.4 | 0.1 | 0.1 |
| Clinical treatment programs - US growth | 4.4% | -17.2% | 16.4% | -61.9% | -16.0% | 375.0% | -30.8% | -32.5% |
| Total Revenues | 0.1 | 0.1 | 0.2 | 0.1 | 0.4 | 0.4 | 0.1 | 0.1 |
| Total Revenues growth | 4.4% | -17.2% | 16.4% | -61.9% | -16.0% | 375.0% | -30.8% | -32.5% |
| Costs and Expenses: | | | | | | | | |
| Production costs | | 0.9 | 0.8 | 0.9 | 0.9 | 1.2 | 1.1 | 1.6 |
| Research and development | 7.0 | 7.7 | 5.7 | 4.7 | 4.8 | 4.1 | 5.1 | 8.0 |
| General and administrative | 13.1 | 8.7 | 8.7 | 7.0 | 6.2 | 6.6 | 7.7 | 7.1 |
| Total Costs and Expenses | 40.1 | 19.0 | 15.3 | 12.6 | 11.9 | 11.9 | 13.9 | 16.8 |
| Operating loss | -19.9 | -18.8 | -15.2 | -12.4 | -11.5 | -11.4 | -13.8 | -16.7 |
| Operating margin | -14129.8% | -13954.1% | -9295.7% | -8887.9% | -3132.4% | -2612.4% | -15004.3% | -12518.8% |
| Gain (Loss) on investments | -1.7 | -0.2 | 0.2 | | | | | |
| Interest and other income | 0.6 | | | | | | | |
| |
| Interest expense and other finance costs | | | | | | | | |
| (Loss) on sale of fixed assets | 0.0 | 0.2 | | | | | | |
| Redeemable warrants valuation adjustment | 0.0 | 0.1 | -0.1 | 1.5 | 1.2 | 2.4 | 1.7 | |
| Gain from sale of Income tax operating losses | 1.5 | 2.3 | 1.2 | 0.9 | | | | |
| Net Loss | -19.4 | -19.1 | -14.4 | -9.4 | -9.8 | -8.3 | -7.5 | -15.2 |
| |
| Basic loss per share | ($0.40) | ($0.40) | ($0.45) | ($2.58) | ($9.77) | ($0.29) | ($0.34) | ($0.77) |
| Diluted loss per share | ($0.40) | ($0.40) | ($0.45) | ($2.58) | ($9.77) | ($0.29) | ($0.34) | ($0.77) |
| Weighted average shares outstanding basic | 48.0 | 47.3 | | | | | | |
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