Analytical testing Partnership Program 2016-2017

Exhibit 10.28

Exova 2395 Speakman Dr. Missisauga Ontario Canada L5K 1B3   Testing. Advising. Assuring		T: +1 ###-###-#### F: +1 ###-###-#### E: ***@*** W: www.exova.com

[*] = Certain confidential information contained in this document, marked by brackets, has been omitted and filed separately with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

Analytical testing Partnership Program 2016-2017

Analytical Testing Partnership Program 2016-2017 For Intersect ENT		Page 2 of 4 Quotation No.: 15-011-383926

EXECUTIVE SUMMARY

Exova’s Health Sciences group has developed a strong relationship with Intersect ENT during the past decade. Over this period, services provided have included method development, method and process validation, contaminant and unknown investigation, characterization of impurities, raw material and finished product testing, and stability program services.

Intersect ENT has had major success in product development, clinical efficacy and approval of its novel stent products. The company is experiencing rapid growth in moving from a purely research organization, to a manufacturing firm with a continuing R&D pipeline.

Exova has made investments to increase our capacity in tandem, so that Intersect ENT can continue to rely on Exova as the vendor of choice for analytical support and development. We appreciate your regular feedback and this has been very valuable in making changes and improvements so that our final product meets your expectations.

Exova is committed to working with Intersect ENT to manage costs and to extend our mutually beneficial and cost effective long term partnership. In this light, for the next 24 months Exova is pleased to offer a pricing arrangement that includes an annual [*] increase to offset inflationary pressures, but retains the same base pricing structure for [*] services which has not been altered for the last seven years.

We are looking forward to continuing to support Intersect ENT for analytical testing development and stability needs.

Approved by:

[*] = Certain confidential information contained in this document, marked by brackets, has been omitted and filed separately with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

Analytical Testing Partnership Program 2016-2017 For Intersect ENT		Page 3 of 4 Quotation No.: 15-011-383926

PRICING

Table 1. Custom Analyses

This 2016 pricing structure includes a [*] inflationary price increase but the base pricing structure remains the same; a [*] increase will also be applied to the 2017 calendar year beginning January 01, 2017. The pricing indicated in the above table is quoted for [*] (please note: turnaround time is defined as delivery of the final Certificate of Analysis by 5:00 PM PT on the day promised). 24 and 72 hour priority service will be accompanied by a surcharge of [*]% and [*]%, respectively.

[*] = Certain confidential information contained in this document, marked by brackets, has been omitted and filed separately with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

Analytical Testing Partnership Program 2016-2017 For Intersect ENT		Page 4 of 4 Quotation No.: 15-011-383926

Table 2. USP/NF/EP/Custom Monograph Testing

Raw Data packages are [*] of the total analytical cost, $[*] minimum and $[*] maximum. The pricing indicated in the above table is quoted for [*] turnaround (please note; turnaround time is defined as delivery of the final certificate of analysis by 5:00 PM PT on the day promised). 24 and 72 hour priority service will be accompanied by a surcharge of [*] and [*], respectively.

TERMS AND CONDITIONS

This quotation is open for acceptance until December 15, 2015, and these prices will be in effect until December 31, 2017. It can be accepted on or before this date by signing and returning to Exova. After the validity date, Exova reserves the right to revise and/or withdraw the quotation as appropriate. This quotation has been prepared exclusively on behalf of Exova and is provided in confidence. The contents of this quotation including pricing information is for the sole consideration of Intersect ENT and cannot be divulged to a third party without the expressed written consent of Exova.

This quotation and the services are governed by the terms and conditions (“the Conditions”) as attached. This quotation may be accepted by signing the enclosed copy in the space provided below and returning it, for receipt by Exova within the time for acceptance given above. It will then constitute an agreement between us (the “Contract”). Please be advised that a purchase order is acceptable for billing purposes only, and the work is governed by the attached terms and conditions.

Accepted by Intersect ENT:

[*] = Certain confidential information contained in this document, marked by brackets, has been omitted and filed separately with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.