Other income was $0.4 million for the year ended December 31, 2010 and $0 for the year ended December 31, 2009. Other income during 2010 represented federal grants we received under the Qualifying Therapeutic Discovery Project Program, net of filing and application fees.
Interest expense was $3.1 million for the year ended December 31, 2010, compared to $2.1 million for the year ended December 31, 2009. The increase of $1.0 million was primarily attributable to charges related to the conversion of all our convertible notes, of which the aggregate amount of principal and accrued interest as of March 30, 2010 was $18.9 million, in connection with the IPO. The increase was partially offset by lower interest accrued on our convertible notes during 2010 compared to 2009, as a result of a full year of interest in 2009 compared to approximately three months of interest in 2010. The interest expense charges consisted primarily of a beneficial conversion feature charge of $1.1 million related to the 30% discount at which the 8% senior convertible notes we issued in October and November 2009 in the aggregate principal amount of $2.6 million, converted into common stock, a write-off of debt discount of $1.1 million in 2010 compared to the amortization of debt discount of $0.5 million in 2009 and a write-off of the remaining amortization of deferred financing fees of $0.4 million in 2010 compared to amortization of deferred financing fees of $0.2 million in 2009.
At December 31, 2010, CorMedix had cash and cash equivalents of $8.3 million, compared to $1.5 million at December 31, 2009. CorMedix believes its currently available cash and cash equivalents will be sufficient to meet its planned clinical development and operating requirements into the first quarter of 2012. The increase in cash and cash equivalents was due to the completion of the IPO in March 2010, which provided proceeds to the Company of approximately $10.5 million, net of underwriting discounts, commissions and offering expenses of approximately $2.1 million.