UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

 

 

 

FORM 8-K

 

 

CURRENT REPORT

 

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): March 24, 2020

 

 

 

NOVAVAX, INC.

(Exact name of registrant as specified in charter)

 

 

 

Delaware   0-26770   22-2816046

(State or Other Jurisdiction

of Incorporation) 

  (Commission File Number)  

(I.R.S. Employer

Identification No.) 

 

21 Firstfield Road

Gaithersburg, Maryland 20878

(Address of Principal Executive Offices, including Zip Code)

 

(240) 268-2000

(Registrant’s telephone number, including area code)

 

(Former name or former address, if changed since last report.)

 

 

 

Securities registered pursuant to Section 12(b) of the Act:

 

Title of each class   Trading Symbol(s)   Name of each exchange on which registered
Common Stock, Par Value $0.01 per share   NVAX   The Nasdaq Global Select Market

 

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

 

¨Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

 

¨Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

 

¨Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

 

¨Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

 

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

 

Emerging growth company ¨

 

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

 

 

 

 

 

 

Item 7.01. Regulation FD Disclosure.

 

On March 24, 2020, Novavax, Inc. (the “Company”) announced positive top-line results of its pivotal Phase 3 clinical trial of NanoFlu™, the Company’s recombinant quadrivalent seasonal influenza vaccine candidate with its proprietary Matrix-M™ adjuvant, as well as information regarding an update for investors on a webcast/conference call presenting such results. Copies of the press release and investor presentation are attached to this Current Report on Form 8-K as Exhibits 99.1 and 99.2, respectively, and incorporated into this Item 7.01 by reference. A copy of the investor presentation will also be accessible on the Company’s website at www.novavax.com under “Investors/Events.”

 

The information in this Item 7.01, including Exhibits 99.1 and 99.2, is being furnished and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section and shall not be deemed incorporated by reference into any registration statement or other document filed pursuant to the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, except as shall be expressly set forth by specific reference in such filing. In addition, the contents of Company’s website are not incorporated by reference into this Current Report on Form 8-K and you should not consider information provided on the Company’s website to be part of this Current Report on Form 8-K.

 

Cautionary Note Regarding Forward-Looking Statements. The press release and investor presentation contain forward-looking statements that involve certain risks and uncertainties that could cause actual results to differ materially from those expressed or implied by these statements. Please refer to the cautionary notes in the press release and investor presentation regarding these forward-looking statements.

 

Item 9.01. Financial Statements and Exhibits.

 

(d)       Exhibits.

 

Exhibit No.   Description
     
99.1   Press Release, dated March 24, 2020.
     
99.2   Investor Presentation of Novavax, Inc.

 

 

 

 

 

SIGNATURES

 

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

 

  Novavax, Inc.
     
     
Date: March 24, 2020 By: /s/ John A. Herrmann III
  Name: John A. Herrmann III
  Title: Senior Vice President, General Counsel and Corporate Secretary

 

 

Exhibit 99.1

 

 

 

Novavax’ NanoFlu Achieves All Primary Endpoints In

Phase 3 Clinical Trial

 

·Trial also achieves statistical significance in key secondary endpoints
·Novavax to submit a U.S. BLA under FDA’s accelerated approval pathway
·Company to host investor conference call today at 8:30 a.m. EDT

 

Gaithersburg, MD, March 24, 2020 – Novavax, Inc. (NASDAQ: NVAX), a late-stage biotechnology company developing next-generation vaccines for serious infectious diseases, today announced positive top-line results of its pivotal Phase 3 clinical trial of NanoFlu™, its recombinant quadrivalent seasonal influenza vaccine candidate with its proprietary Matrix-M™ adjuvant, in adults aged 65 and older. Using the Food and Drug Administration’s (FDA) criteria for accelerated approval of seasonal influenza vaccines, the trial evaluated the immunogenicity and safety of NanoFlu compared to Fluzone® Quadrivalent, a U.S.-licensed quadrivalent influenza vaccine.

 

NanoFlu Phase 3 Primary Objectives

 

The trial’s primary objectives were to demonstrate non-inferior immunogenicity of NanoFlu compared to Fluzone Quadrivalent using the day 28 ratio of geometric mean titers (GMT) and the difference in seroconversion rates (SCR), as well as the overall safety of NanoFlu. Immunogenicity was measured by hemagglutination inhibition (HAI) assays using egg-derived reagents.

 

·NanoFlu achieved the primary endpoints, both GMT and SCR, for all four strains included in the vaccine.

 

·NanoFlu was well-tolerated and had a safety profile comparable to Fluzone Quadrivalent with a modest increase in local adverse events (AEs).

 

“With these data, we now have a clear path forward to licensure with our differentiated recombinant influenza vaccine,” said Stanley C. Erck, President and Chief Executive Officer of Novavax. “These strong Phase 3 results align with and validate our previous clinical trials, in which NanoFlu showed higher HAI antibody responses than the leading flu vaccine for older adults. We expect that both Fast Track designation and the accelerated approval pathway from the FDA will help Novavax bring NanoFlu to market as quickly as possible to address the serious public health threat of influenza.”

 

NanoFlu Phase 3 Secondary Objectives

 

The trial’s key secondary endpoints assessed GMT and SCR, but with an HAI assay based on wild-type reagents, which are expected to provide a more accurate assessment of clinically relevant HAI antibody responses against circulating wild-type viruses.

 

 

 

 

·NanoFlu demonstrated significantly higher GMT and SCR than Fluzone Quadrivalent across all four strains included in the vaccine.
·24%-66% higher GMT responses; and
·11.4-20.4 higher SCR percentage points.

 

·NanoFlu also demonstrated significantly higher GMT and SCR than Fluzone Quadrivalent for four tested drifted H3N2 strains not included in the vaccine but circulating this year.
·34%-41% higher GMT responses; and
·14.1-16.8 higher SCR percentage points

 

“In addition to meeting the primary objectives, we are very pleased to report that NanoFlu also met or exceeded its secondary endpoints for all four strains using our proprietary HAI assay based upon wild-type reagents,” said Gregory Glenn, M.D., President of Research and Development of Novavax. “NanoFlu demonstrated significant improvement against four drifted H3N2 strains that are co-circulating this year. These data, similar to what was shown in our Phase 2 clinical trial, demonstrate that NanoFlu overcomes issues related to egg-adaptation and antigenic drift. We extend our sincere appreciation to those who volunteered for this important study and to our clinical partners who worked so quickly and diligently on this trial.”

 

Webcast Conference Call

 

Novavax will host a webcast/conference call today at 8:30 a.m. ET. The webcast can be accessed via a link on the home page of the Novavax website (novavax.com) or through the “Investor Info”/“Events” tab on the Novavax website. Listeners who wish to ask questions or don’t have internet access can dial-in to the conference call at (877) 212-6076 (domestic) or (707) 287-9331 (international) and use passcode 4498251.

 

A replay of the webcast will be available on the Novavax website until June 24, 2020 and a replay of the conference call only will be available starting at 11:30 a.m. ET on March 24, 2020 until 11:30 a.m. ET on March 31, 2020. To access the conference call replay, dial (855) 859-2056 (domestic) or (404) 537-3406 (international) and use passcode 4498251.

 

About Phase 3 Clinical Trial

 

The trial enrolled 2,652 healthy older adults across 19 U.S. clinical sites. Trial participants received either NanoFlu or the comparator, both of which were formulated with the four influenza strains recommended for the 2019-2020 Northern hemisphere influenza season. Participants will be followed for approximately one year after injection, with primary immunogenicity analyses of the Day 28 sera samples.

 

 

 

 

About NanoFlu™ and Matrix-M™

 

NanoFlu is a recombinant hemagglutinin (HA) protein nanoparticle influenza vaccine produced by Novavax in its SF9 insect cell baculovirus system. NanoFlu uses HA amino acid protein sequences that are the same as the recommended wild-type circulating virus HA sequences. The qNIV vaccine antigens were derived from A/Brisbane 02/2018 H1N1, A/Kansas 14/2017 H3N2, B/Maryland 15/2016 and B/Phuket 3073/2013. NanoFlu contains Novavax’ patented saponin-based Matrix-M adjuvant, which has demonstrated a potent and well-tolerated effect by stimulating the entry of antigen-presenting cells into the injection site and enhancing antigen presentation in local lymph nodes.

 

About Novavax

 

Novavax, Inc. (Nasdaq:NVAX), is a late-stage biotechnology company that promotes improved health globally through the discovery, development, and commercialization of innovative vaccines to prevent serious infectious diseases. NanoFlu™, its quadrivalent influenza nanoparticle vaccine, met primary and secondary endpoints in its pivotal Phase 3 clinical trial. ResVax™, its RSV vaccine for infants via maternal immunization, is the only vaccine to demonstrate efficacy in a Phase 3 clinical trial. Novavax recently initiated development of a vaccine program against COVID-19. Novavax is a leading innovator of recombinant vaccines; its proprietary recombinant technology platform combines the power and speed of genetic engineering to efficiently produce a new class of highly immunogenic nanoparticles addressing urgent global health needs.

 

For more information, visit www.novavax.com and connect with us on Twitter and LinkedIn.

 

Forward-Looking Statements

 

Statements herein relating to the future of Novavax and the ongoing development of its vaccine and adjuvant products are forward-looking statements. Novavax cautions that these forward-looking statements are subject to numerous risks and uncertainties, which could cause actual results to differ materially from those expressed or implied by such statements. These risks and uncertainties include those identified under the heading “Risk Factors” in the Novavax Annual Report on Form 10-K for the year ended December 31, 2019, as filed with the Securities and Exchange Commission (SEC). We caution investors not to place considerable reliance on the forward-looking statements contained in this press release. You are encouraged to read our filings with the SEC, available at sec.gov, for a discussion of these and other risks and uncertainties. The forward-looking statements in this press release speak only as of the date of this document, and we undertake no obligation to update or revise any of the statements. Our business is subject to substantial risks and uncertainties, including those referenced above. Investors, potential investors, and others should give careful consideration to these risks and uncertainties.

 

 

 

 

Contacts:

 

Investors

Novavax, Inc.

Erika Trahan

ir@novavax.com

240-268-2022

 

Westwicke

John Woolford

john.woolford@westwicke.com

443-213-0506

 

Media

Brandzone/KOGS Communication

Edna Kaplan

kaplan@kogspr.com

617-974-8659

 

 

 

 

 

 

Exhibit 99.2

 

 

1 novavax.com NanoFlu Phase 3 clinical trial goals and design Primary objectives • To demonstrate the non - inferior immunogenicity of NanoFlu, relative to Fluzone® Quadrivalent, in terms of hemagglutination inhibition (HAI) antibody responses to all vaccine homologous influenza strains at Day 28. • To describe the safety profile of NanoFlu and Fluzone Secondary objectives • To describe the immunogenicity with both egg - propagated virus and wild - type VLP reagents to all four vaccine - homologous influenza strains and to select drifted strains at Day 28. • To describe the immunogenicity in terms of microneutralization (MN) responses to vaccine - homologous and/or antigenically drifted influenza strains at Day 0 and 28 • To describe the quality and amplitude of cell - mediated immune (CMI) responses in a subset of participants Design Randomized, observer - blinded, active - comparator controlled trial Vaccine strains • WHO - recommended 2019 - 2020 Northern Hemisphere influenza vaccine strains. A/Brisbane (H1N1); A/Kansas (H3N2); B/Maryland (Victoria); B/Phuket (Yamagata) Investigational and comparator vaccines • Hemagglutinin nanoparticle influenza vaccine, quadrivalent with Matrix - M ™ adjuvant (quad - NIV) [NanoFlu] • Quadrivalent inactivated influenza vaccine (IIV4) [Fluzone] Stratification • History of receipt of 2018 - 2019 influenza vaccine Participants • 2,650 clinically stable adults > 65 years of age • Randomized 1:1 (NanoFlu : Fluzone), Single vaccination at Day 0 Study sites • 19 U.S. sites Length of study participation • 1 year (safety assessment through 1 year)

 

 

2 novavax.com NanoFlu Phase 3 clinical trial conclusions Primary endpoint met: demonstrated immunologic non - inferiority to Fluzone in terms of hemagglutination inhibition (HAI) antibody responses (assayed with egg - derived virus reagents ) against all four vaccine homologous strains (per CBER criteria). Statistically significant higher HAI antibody responses (assayed with wild - type VLP reagents ) compared to Fluzone: • 24 — 66% improved Day 28 GMTs against homologous strains • 34 — 41% improved Day 28 GMTs against drifted H3N2 strains • 11.4 — 20.4% increased Day 28 seroconversion rate against homologous strains • 14.1 — 16.8% increased Day 28 seroconversion rate against drifted H3N2 strains NanoFlu was well - tolerated

 

 

3 novavax.com NanoFlu Fluzone Quad D28 GMT Ratio Assay Strain D28 GMT D28 GMT (NanoFlu / Fluzone) 95% CI HAI: EGG A/Brisbane/02/2018 (H1N1) pdm09 (Homologous) 49.3 45.0 1.09 ( 1.03, 1.15) A/Kansas/14/2017 (H3N2) (Homologous) 151.5 126.8 1.19 ( 1.11, 1.27) B/Maryland/15/2016 (Vic) (Homologous) 110.7 106.3 1.03 ( 0.99, 1.07) B/Phuket/3073/2013 (Yam) (Homologous) 168.5 133.9 1.23 ( 1.16, 1.29) Immunogenicity : Egg - or wild - type VLP - based Day 28 HAI GMTs and GMT ratios (NanoFlu / Fluzone) Success: All 95% CI lower bounds are ≥ 0.67 x GMT ratio success criteria met x NanoFlu: 3 — 23% improved responses using egg - based HAI

 

 

4 novavax.com NanoFlu Fluzone Quad D28 GMT Ratio Assay Strain D28 GMT D28 GMT (NanoFlu / Fluzone) 95% CI HAI: EGG A/Brisbane/02/2018 (H1N1) pdm09 (Homologous) 49.3 45.0 1.09 ( 1.03, 1.15) A/Kansas/14/2017 (H3N2) (Homologous) 151.5 126.8 1.19 ( 1.11, 1.27) B/Maryland/15/2016 (Vic) (Homologous) 110.7 106.3 1.03 ( 0.99, 1.07) B/Phuket/3073/2013 (Yam) (Homologous) 168.5 133.9 1.23 ( 1.16, 1.29) HAI: VLP A/Brisbane/02/2018 (H1N1) pdm09 (Homologous) 76.6 62.7 1.24 ( 1.17, 1.32) A/Kansas/14/2017 (H3N2) (Homologous) 153.6 90.7 1.66 ( 1.53, 1.79) B/Maryland/15/2016 (Vic) (Homologous) 62.8 47.2 1.32 ( 1.26, 1.39) B/Phuket/3073/2013 (Yam) (Homologous) 118.3 78.4 1.47 ( 1.40, 1.55) Immunogenicity : Egg - or wild - type VLP - based Day 28 HAI GMTs and GMT ratios (NanoFlu / Fluzone) x NanoFlu: 24 — 66% improved responses using VLP - based HAI x “Superiority” criteria met for homologous H3N2 (66% better)

 

 

5 novavax.com NanoFlu Fluzone Quad D28 GMT Ratio Assay Strain D28 GMT D28 GMT (NanoFlu / Fluzone) 95% CI HAI: EGG A/Brisbane/02/2018 (H1N1) pdm09 (Homologous) 49.3 45.0 1.09 ( 1.03, 1.15) A/Kansas/14/2017 (H3N2) (Homologous) 151.5 126.8 1.19 ( 1.11, 1.27) B/Maryland/15/2016 (Homologous) 110.7 106.3 1.03 ( 0.99, 1.07) B/Phuket/3073/2013 (Homologous) 168.5 133.9 1.23 ( 1.16, 1.29) HAI: VLP A/Brisbane/02/2018 (H1N1) pdm09 (Homologous) 76.6 62.7 1.24 ( 1.17, 1.32) A/Kansas/14/2017 (H3N2) (Homologous) 153.6 90.7 1.66 ( 1.53, 1.79) B/Maryland/15/2016 (Homologous) 62.8 47.2 1.32 ( 1.26, 1.39) B/Phuket/3073/2013 (Homologous) 118.3 78.4 1.47 ( 1.40, 1.55) A/California (“Drifted” H3N2) 115.0 80.6 1.41 ( 1.33, 1.50) A/Cardiff (“Drifted” H3N2) 63.9 45.4 1.34 ( 1.27, 1.43) A/Netherlands (“Drifted” H3N2) 102.3 74.7 1.38 ( 1.30, 1.46) A/South Australia (“Drifted” H3N2) 98.1 70.4 1.36 ( 1.28, 1.44) Immunogenicity : Egg - or wild - type VLP - based Day 28 HAI GMTs and GMT ratios (NanoFlu / Fluzone) x NanoFlu: 34 — 41% improved responses on drifted H3N2s using VLP - based HAI

 

 

6 novavax.com NanoFlu Fluzone Quad Absolute SCR Difference Assay Strain SCR SCR NanoFlu - Fluzone Quad 95% CI HAI:EGG A/Brisbane/02/2018 (H1N1) pdm09 (Homologous) 22.0% (282/1280) 17.0% (219/1286) 5.0 ( 1.9, 8.1) A/Kansas/14/2017 (H3N2) (Homologous) 41.8% (535/1280) 34.4% (443/1286) 7.3 ( 3.6, 11.1) B/Maryland/15/2016 (Vic) (Homologous) 11.2% (143/1280) 10.7% (137/1286) 0.5 ( - 1.9, 2.9) B/Phuket/3073/2013 (Yam) (Homologous) 31.3% (401/1280) 22.9% (294/1286) 8.5 ( 5.0, 11.9) Immunogenicity: Egg - or wild - type VLP - based Day 28 HAI SCR and SCR difference (NanoFlu - Fluzone) Success: All 95% CI lower bounds are ≥ - 10 x Seroconversion (SCR) difference success criteria met x NanoFlu: 0.5 — 8.5% increased SCR using egg - based HAI

 

 

7 novavax.com NanoFlu Fluzone Quad Absolute SCR Difference Assay Strain SCR SCR NanoFlu - Fluzone Quad 95% CI HAI:EGG A/Brisbane/02/2018 (H1N1) pdm09 (Homologous) 22.0% (282/1280) 17.0% (219/1286) 5.0 ( 1.9, 8.1) A/Kansas/14/2017 (H3N2) (Homologous) 41.8% (535/1280) 34.4% (443/1286) 7.3 ( 3.6, 11.1) B/Maryland/15/2016 (Vic) (Homologous) 11.2% (143/1280) 10.7% (137/1286) 0.5 ( - 1.9, 2.9) B/Phuket/3073/2013 (Yam) (Homologous) 31.3% (401/1280) 22.9% (294/1286) 8.5 ( 5.0, 11.9) HAI:VLP A/Brisbane/02/2018 (H1N1) pdm09 (Homologous) 32.7% (419/1280) 21.4% (275/1286) 11.4 ( 7.9, 14.7) A/Kansas/14/2017 (H3N2) (Homologous) 69.8% (894/1280) 49.5% (636/1286) 20.4 ( 16.6, 24.1) B/Maryland/15/2016 (Vic) (Homologous) 25.1% (321/1280) 13.5% (173/1286) 11.6 ( 8.6, 14.6) B/Phuket/3073/2013 (Yam) (Homologous) 35.4% (453/1280) 17.7% (228/1286) 17.7 ( 14.3, 21.0) Immunogenicity: Egg - or wild - type VLP - based Day 28 HAI SCR and SCR difference (NanoFlu - Fluzone) x NanoFlu: 11.4 — 20.4% increased SCR using VLP - based HAI

 

 

8 novavax.com NanoFlu Fluzone Quad Absolute SCR Difference Assay Strain SCR SCR NanoFlu - Fluzone Quad 95% CI HAI:EGG A/Brisbane/02/2018 (H1N1) pdm09 (Homologous) 22.0% (282/1280) 17.0% (219/1286) 5.0 ( 1.9, 8.1) A/Kansas/14/2017 (H3N2) (Homologous) 41.8% (535/1280) 34.4% (443/1286) 7.3 ( 3.6, 11.1) B/Maryland/15/2016 (Vic) (Homologous) 11.2% (143/1280) 10.7% (137/1286) 0.5 ( - 1.9, 2.9) B/Phuket/3073/2013 (Yam) (Homologous) 31.3% (401/1280) 22.9% (294/1286) 8.5 ( 5.0, 11.9) HAI:VLP A/Brisbane/02/2018 (H1N1) pdm09 (Homologous) 32.7% (419/1280) 21.4% (275/1286) 11.4 ( 7.9, 14.7) A/Kansas/14/2017 (H3N2) (Homologous) 69.8% (894/1280) 49.5% (636/1286) 20.4 ( 16.6, 24.1) B/Maryland/15/2016 (Vic) (Homologous) 25.1% (321/1280) 13.5% (173/1286) 11.6 ( 8.6, 14.6) B/Phuket/3073/2013 (Yam) (Homologous) 35.4% (453/1280) 17.7% (228/1286) 17.7 ( 14.3, 21.0) A/California (“Drifted” H3N2) 37.1% (475/1280) 20.5% (264/1286) 16.6 ( 13.1, 20.0) A/Cardiff (“Drifted” H3N2) 32.7% (419/1280) 18.6% (239/1286) 14.1 ( 10.8, 17.5) A/Netherlands (“Drifted” H3N2) 38.4% (492/1280) 21.7% (278/1284) 16.8 ( 13.3, 20.2) A/South Australia (“Drifted” H3N2) 34.4% (440/1280) 19.6% (252/1284) 14.7 ( 11.3, 18.1) Immunogenicity: Egg - or wild - type VLP - based Day 28 HAI SCR and SCR difference (NanoFlu - Fluzone) x NanoFlu: 14.1 — 16.8% increased SCR using VLP - based HAI

 

 

9 novavax.com Topline safety N 1333 1319 Counts (%) of Subjects with Events Any treatment emergent adverse event ( TEAE) 659 (49.4) 551 (41.8) Any Solicited TEAE 551 (41.3) 420 (31.8) Local solicited 372 (27.9) 243 (18.4) Severe local solicited 8 (0.6) 2 (0.2) Systemic Solicited 369 (27.7) 292 (22.1) Severe systemic solicited 15 (1.1) 11 (0.8) Unsolicited TEAE 248 (18.6) 241 (18.3) Severe unsolicited 23 (1.7) 12 (0.9) Severe & related unsolicited 10 (0.8) 2 (0.2) Medically - attended unsolicited 99 (7.4) 104 (7.9) Serious adverse events (SAEs) 11 (0.8) 5 (0.4) NanoFlu Fluzone Quad (SD) Safety events (through Day 28)

 

 

10 novavax.com NanoFlu Phase 3 clinical trial conclusions Primary endpoint met: demonstrated immunologic non - inferiority to Fluzone in terms of hemagglutination inhibition (HAI) antibody responses (assayed with egg - derived virus reagents ) against all four vaccine homologous strains (per CBER criteria). Statistically significant higher HAI antibody responses (assayed with wild - type VLP reagents ) compared to Fluzone: • 24 — 66% improved Day 28 GMTs against homologous strains • 34 — 41% improved Day 28 GMTs against drifted H3N2 strains • 11.4 — 20.4% increased Day 28 seroconversion rate against homologous strains • 14.1 — 16.8% increased Day 28 seroconversion rate against drifted H3N2 strains NanoFlu was well - tolerated