In the three-com­pa­ny race to de­vel­op a new uter­ine fi­broid treat­ment, Ob­sE­va long lagged be­hind Ab­b­Vie and My­ovant. Still, they hoped that bet­ter ef­fi­ca­cy — in­clud­ing a 93.9% re­sponse rate in one Phase III tri­al — could ul­ti­mate­ly de­liv­er bet­ter sales.

Now, though, the sec­ond of those Phase III stud­ies is out, and it has brought the Swedish biotech back to earth.

In the sec­ond of their Phase III tri­als, 75.5% of pa­tients who took Ob­sE­va’s ex­per­i­men­tal tablet lin­zagolix plus a hor­mone saw their bleed­ing re­duced by at least 50% and at least 80 ml af­ter 24 weeks. Pool­ing those re­sults with new da­ta from their first Phase III tri­al — which showed a 93.9% re­sponse rate at 24 weeks and a 91.6% re­sponse rate at 52 weeks — Ob­sE­va cal­cu­lat­ed a col­lec­tive 84.7% re­spon­der rate for pa­tients tak­ing their ther­a­py and said the da­ta “con­firm po­ten­tial best-in-class” sta­tus.

“These ex­cel­lent da­ta move us clos­er to the po­ten­tial com­mer­cial­iza­tion of Ysel­ty and our im­me­di­ate pri­or­i­ty is to progress our reg­u­la­to­ry fil­ings,” Ernest Loumaye, Ob­sE­va CEO and co-founder said in a state­ment, us­ing the brand­ed name for his drug.

Yet some in­vestors and an­a­lysts were dis­ap­point­ed, not­ing that these new re­sults erase the edge that the first tri­al seemed to give Ob­sE­va. 75.5% falls right in line with the re­sults from Ab­b­Vie and My­ovant. Ab­b­vie had a 68.5% re­sponse rate in one Phase III tri­al and a 76.2% re­sponse rate in the sec­ond. My­ovant saw re­sponse rates of 71.2% and 73.4%.

In fact, SVB Leerink’s Ami Fa­dia wrote in a note to in­vestors that be­cause Ob­sE­va had high place­bo re­sponse in both tri­als. the com­pa­ny now has the worst place­bo-ad­just­ed re­sponse of any of the three.

“We be­lieve the place­bo-ad­just­ed re­sponse rate will be a key met­ric that in­vestors pay at­ten­tion to, and the PRIM­ROSE1 re­sults on that mea­sure like­ly fell short of ex­pec­ta­tions,” Fa­dia wrote, not­ing their own Ob­sE­va mod­el is now un­der re­view.

The mar­ket agreed, cut­ting Ob­sE­va’s stock $OB­SV by 40%, or $2.75, Mon­day morn­ing.

Even be­fore the new tri­al, an­a­lysts had ex­pressed reser­va­tions about Ob­sE­va’s ap­par­ent ef­fi­ca­cy. In De­cem­ber, Baird’s Bri­an Sko­r­ney chalked up their high score to a 29.4% place­bo re­sponse rate, far high­er than those seen in their two com­peti­tors’ tri­als. “We think the re­sound­ing take­away here is that the ef­fi­ca­cy pro­files of these 3 … in­hibitors are es­sen­tial­ly the same,” he wrote in a note to in­vestors.

If these drugs are ef­fec­tive­ly the same, Sko­r­ney bet that the first ones out of the gate will es­tab­lish a beach-head and gar­ner the most sales. That would spell bad news for Ob­sE­va. Tim­ing-wise, they now sit in third place. Ab­b­Vie’s drug has al­ready been ap­proved and My­ovant sub­mit­ted an NDA in June, while Ob­sE­va has yet to file an ap­pli­ca­tion. Known as GnRH in­hibitors, these drugs block a hor­mone re­cep­tor in the body.

Some an­a­lysts, though, bet that de­spite some ini­tial con­cerns, safe­ty could ul­ti­mate­ly be Ob­sE­va’s ad­van­tage. When the FDA ap­proved Ab­b­Vie’s drug, Ori­ahnn, they al­so put strict lim­its on its use af­ter mul­ti­ple pa­tients in their tri­al had throm­bot­ic events, in­clud­ing a pul­monary em­bolism. These like­ly came from ex­tra hor­mone treat­ments, known as add-back ther­a­py, pa­tients take to stop the menopause-like symp­toms GnRH in­hibitors can cause.

That’s part­ly why Ob­sE­va in­clud­ed an arm on both tri­als where pa­tients took a small­er dose of the drug and didn’t re­ceive the add-back ther­a­py. In the com­pa­ny’s first tri­al, a lit­tle over half of those pa­tients saw their bleed­ing cut in half. That could make it a good can­di­date for pa­tients with oth­er co-mor­bidi­ties, Fa­dia and oth­er an­a­lysts wrote. The new study showed a 56.6% rate of pa­tients on the no-add-back treat­ment arm, but it al­so had a 35% rate in place­bo, cut­ting the place­bo-ad­just­ed rate to just 21.4%. With new 52-week da­ta out, there were al­so ques­tions about how long the ther­a­py would last.

“We still view the pro­file of both the low dose and the high dose as ap­prov­able,” Fa­dia wrote, “al­though we see po­ten­tial ques­tions com­ing up re­gard­ing the treat­ment du­ra­tion on the la­bel and the com­mer­cial vi­a­bil­i­ty for the low dose.”

Since losing a controversial court case over orphan drug exclusivity last year, the FDA’s Office of Orphan Products Development has remained entirely silent on orphan exclusivity for any product approved since last November, leaving many sponsors in limbo on what to expect.

That silence means that for more than 70 orphan-designated indications for more than 60 products, OOPD has issued no public determination on the seven-year orphan exclusivity in the Orange Book, and no new listings of orphan exclusivity appear in OOPD’s searchable database, as highlighted recently by George O’Brien, a partner in Mayer Brown’s Washington, DC office.

The Drugs for Neglected Diseases initiative (DNDi) and Sanofi today said that their potential sleeping sickness treatment saw success rates of up to 95% from a Phase II/III study investigating the safety and efficacy of single-dose acoziborole.

The potentially transformative treatment for sleeping sickness would mainly be targeted at African countries, according to data published today in The Lancet Infectious Diseases medical journal. The clinical trial was led by DNDi and its partners in the Democratic Republic of the Congo (DRC) and Guinea, with the authors noting: