Less than a month af­ter Prax­is Pre­ci­sion Med­i­cines hit Wall Street with an up­sized IPO, the FDA has slapped a clin­i­cal hold on its lead can­di­date for ma­jor de­pres­sive dis­or­der (MDD), send­ing shares spi­ral­ing.

With­out pro­vid­ing much in­for­ma­tion, the FDA said in an email that it re­viewed Prax­is’ IND for its Phase II/III tri­al, and is plac­ing a full clin­i­cal hold on the study. More de­tails should come in the next 30 days, ac­cord­ing to the email. Prax­is says it has reached out to the agency, which said it isn’t done fi­nal­iz­ing com­ments.

“The FDA has not pro­vid­ed any rea­son for the clin­i­cal hold,” Prax­is said in a state­ment. Ac­cord­ing to an S-1/A filed on Oct 15, the study would have sat­is­fied one of two reg­is­tra­tional tri­als re­quired by the FDA to sup­port clin­i­cal ef­fi­ca­cy. The biotech’s stock $PRAX plunged more than 26% af­ter the news broke on Tues­day.

Cowen an­a­lysts aren’t wor­ried, though. In a note to in­vestors on Tues­day, an­a­lysts Ritu Bar­al and Ly­la Youssef said they be­lieve the hold “should be re­solved in short or­der giv­en the con­tin­ued clean pre­clin­i­cal and clin­i­cal safe­ty pro­file.” The can­di­date, PRAX-114, is cur­rent­ly in an on­go­ing Phase IIa tri­al in Aus­tralia. Part A en­rolled 33 MDD pa­tients, and ear­ly da­ta sug­gest “rapid, marked im­prove­ments in de­pres­sion scores” af­ter two weeks of treat­ment, ac­cord­ing to the an­a­lysts. Af­ter one week, pa­tients showed LS mean Hamil­ton De­pres­sion Rat­ing Scale im­prove­ments of 15 to 19 points across three dose groups.

The can­di­date, GA­BA pos­i­tive al­losteric mod­u­la­tor, is al­so in Phase II tri­als for per­i­menopausal de­pres­sion. The field is a tough one, with sci­en­tists strug­gling for years to de­vel­op bet­ter an­ti-de­pres­sants. Last De­cem­ber, Sage Ther­a­peu­tics’ MDD drug flopped in a large tri­al, cost­ing the com­pa­ny $6 bil­lion in mar­ket cap and forc­ing it to cut half of em­ploy­ees.

If PRAX-114 gets ap­proved, Cowen pre­dicts its US sales po­ten­tial will  be in the $3 bil­lion range.

Prax­is emerged from stealth mode this spring, with $100 mil­lion and two drugs in Phase II. It ini­tial­ly set out to iden­ti­fy mu­ta­tions that cause epilep­sy in pa­tients who didn’t in­her­it the dis­ease, and is now ap­ply­ing those dis­cov­er­ies to oth­er CNS dis­eases, like de­pres­sion, move­ment dis­or­ders and pain syn­dromes. In Ju­ly, Prax­is bagged an­oth­er $110 mil­lion in a Se­ries C1 led by Even­tide As­set Man­age­ment.

Even­tide holds 9.4% of Prax­is’ stock, ac­cord­ing to the S-1/A. Black­stone, No­vo Hold­ings and Vi­da Ven­tures, which al­so kicked in on the round, have 23.1%, 6/6% and 7.3% re­spec­tive­ly.

Back in Au­gust, Prax­is filed for a $100 mil­lion IPO. It end­ed up bring­ing in $190 mil­lion, from $10 mil­lion shares priced at $19 apiece — a buck high­er than the $17 to $18 range. Be­tween $70 to $80 mil­lion was tagged for PRAX-114.

More than a year after the FDA clamped down on Larimar Therapeutics with a clinical hold on its lead drug, the biotech thinks it has a way to get that lifted — and an answer could come next quarter if all goes to plan.

Amid a 15-month setback, the biotech plans on filing a complete response to the FDA’s concerns over its drug, CTI-1601, sometime this quarter, which is supposed to elicit an answer from the agency within 30 days, per the regulator.

Amgen is the latest pharma company to appear on the radar of Senate Finance Committee Chair Ron Wyden (D-OR), who is investigating the way pharma companies are using subsidiaries in low- or zero-tax countries to lower their tax bills.

Like its peers Merck, AbbVie and Bristol Myers Squibb, Wyden notes how Amgen uses its Puerto Rico operations to consistently pay tax rates that are substantially lower than the U.S. corporate tax rate of 21%, with an effective tax rate of 10.7% in 2020 and 12.1% in 2021.