Note 7 - Note Payable

6 Months Ended

Jun. 30, 2018

Notes to Financial Statements

Debt Disclosure [Text Block]

7.

         Note Payable

On

February 28, 2018,

we entered into a Senior Note Purchase Agreement with Georgia Research Alliance, Inc. (GRA) pursuant to which we issued a

five

-year Senior Promissory Note (the “Note”) to GRA in exchange for

$50,000.

The Note bears an annual interest rate of

5%,

payable monthly, with principal repayments beginning in the

second

year. Principal repayments are expected to be $-

0

- in

2018,

$10,417

in

2019,

$12,500

in

2020,

2021

and

2022,

and

$2,083

in

2023.

In connection with the Note, we also issued to GRA a

five

-year warrant to purchase

178,571

shares of our common stock (see Note

9

). Interest expense related to the Note for the

three

-month and

six

-month periods ended

June 30, 2018

was

$625

and

$833,

respectively.