Under the new agreement, the lender will receive 10% interest plus 15% of the appreciation above 33p on 10mln shares held by Amphion in antibiotic developer Motif Bio PLC (LON:MTIF).
Following drawdown of the new funds, the balance on the loan facility will be US$4.23mln, a sum that becomes payable along with accrued interest on 30 September 2019.
Motif Bio shares currently trade at 30.35p and at the current date, their value is sufficient to cover the outstanding balance of the facility, said Amphion.
Under the facility's terms, Amphion cannot sell shares in Polarean Imaging PLC (LON:POLX), another of its listed portfolio companies, without the facility lenders' consent.
Amphion added it remains cash constrained and continues to consider both its short-term and medium-term funding options.
Broker Northland added that the extension of the loan facility allows scope for milestone achievement regarding Amphion’s partner companies, and prevents an early exit of the shares.
"Motif Bio recently submitted a New Drug Application (NDA) to the FDA for iclaprim, its antibiotic candidate.
"The FDA has set a target decision date in February 2019 and, if approved, Motif is targeting a US commercial launch in H1 19.
"In the meantime, Motif is preparing for a commercial launch later in 2019, by seeking commercialisation partners for its product candidate."