HilleVax to discontinue development of norovirus vaccine for infants; shares plummet (updated)

Vaxart

08/07/2024 16:02

(Adds trial details in paragraph 3, analyst comment in
paragraph 8, background in paragraphs 9-10)
       July 8 (Reuters) - Shares of HilleVax  HLVX.O  plunged
as much as 87.6% to a record low of $1.75 on Monday after the
biotech company said it will discontinue the development of its
norovirus vaccine candidate for infants.
    The vaccine, named HIL-214, showed an efficacy of only 5%,
failing to meet the main goal in the mid-stage study conducted
on more than 2,800 infants. It also did not show any clinical
benefits across secondary goals of the study.
    The study's main goal was efficacy against moderate or
severe acute gastroenteritis events due to two norovirus
variants, GI.1 or GII.4. But the company said the vaccine
candidate's efficacy may have been hit due to multiple emerging
types of the GII.4 strain.
    HilleVax said it will discontinue further development of
HIL-214 in infants, and will explore whether it can continue the
same in adults.
    The company said it will also examine whether to develop
HIL-216, its other experimental vaccine, in adults after the
trial failure.
    HilleVax acquired the rights to develop and commercialize
HIL-216 outside Greater China from Chengdu Kanghua Biological
Products  300841.SZ  in January.
    Despite the trial failure in infants, Leerink Partners
analyst David Risinger was optimistic about HilleVax's two
candidates in adults.
    "Norovirus vaccines may offer protection for adults
effectively as a booster, since virtually all adults have been
exposed to norovirus in their lifetimes," Risinger said.
    Norovirus is one of the leading causes of vomiting, diarrhea
and other foodborne illnesses. It is estimated to cause about
685 million cases and roughly 200,000 deaths globally each year,
according to the World Health Organization. Low-income countries
are the worst hit.
    In the United States, norovirus is responsible for nearly 1
million pediatric medical care visits annually, according to the
U.S. Centers for Disease Control and Prevention.
    Currently, Moderna  MRNA.O  and Vaxart  VXRT.O  are also
developing norovirus vaccines.

 (Reporting by Puyaan Singh in Bengaluru; Editing by Shreya
Biswas)
 ((Puyaan.Singh@thomsonreuters.com))