Biopharmaceutical company Opthea (ASX:OPT) said its cash balance fell to $167.5 million in the quarter ended Sept. 30 from $172.5 million in the quarter ended June 30, according to a Thursday filing with the Australian Securities Exchange.

The company said the decrease was mainly due to the receipt of the retail entitlement finalized in July, which offset the operational spend of $39.8 million for two clinical trials.

Cash receipts increased by 175% to $2.2 million, from $800,000 in the previous quarter, while net operating cash outflow increased to $41.2 million from the previous quarter's $38.6 million, the filing said.