How should we think about sequential Vafseo growth in 2026 relative to inventory-adjusted Q4 demand, and could VOICE data accelerate uptake? How operationalized is Vafseo access at DaVita?
Management is not guiding on revenue. Setting aside inventory swings, demand has been roughly flat (~$12M Q2, ~$12M Q3, ~$11M Q4) and they now expect and are seeing growth off that base, but steady rather than a hockey stick, similar to the measured nephrology adoption seen in the historical Renagel launch. Published, peer-reviewed data (ASN outcomes, the cost analysis, later VOICE and VOCAL) is what will drive utilization once medical affairs can use it. DaVita has made the product widely available across its network and is starting with its >30,000-patient home dialysis population, leaving prescribing decisions to physicians, so Akebia's field teams must educate and sell.
How are second and third refill rates trending, and what about anemia manager education?
First refill improved from ~75% historically to ~91% in Q4's small observed-dosing subset and ~87% in the larger January cohort. That high adherence is continuing into the second prescription, against an underlying ~2-4% monthly discontinuation from comorbidities and transplants. Moving patients from daily to observed in-center dosing is driving restarts of previously non-compliant patients. On education, Akebia expanded its medical affairs / MSL group to deliver the clinical data to physicians and anemia managers, and dialysis organizations (including DaVita's centralized anemia management model) are actively participating.
How is AKB-9090 mechanistically differentiated from prior HIF inhibitors like vadadustat?
AKB-9090 has different pharmacokinetics and structure. Vadadustat preferentially targets the liver where erythropoietin is made, while 9090 has more widespread tissue penetration into the lung and kidney. In non-clinical ischemia-reperfusion injury models 9090 was clearly the best compound, an indication where vadadustat likely would not work; it comes down to structure and PK.
What does success look like for the VOCAL study, and how important is the red blood cell sub-study?
VOCAL is a 350-patient study DaVita wanted to run in its own units to operationalize and confirm Vafseo is as safe and effective as the ESAs (Mircera) they use today. The primary endpoint is non-inferiority for hemoglobin control; management suspects superiority on some hemoglobin-related safety endpoints (less rapid rises, fewer high hemoglobins, fewer dose adjustments) though those are pre-specified, not primary. The RBC sub-study is expected to be important in showing Vafseo's cells are different (bigger, more hemoglobin, more uniform width distribution), giving physicians a mechanistic reason to believe the death/hospitalization benefits.
Have you reactivated the IND for AKB-097, and did you change the protocol from what Q32 Bio had aligned with FDA?
The IND has not been reactivated yet. The protocol is fundamentally the same one FDA agreed to with Q32 Bio, but it is being reworked to be simpler and less operationally complex to ease recruitment; the company will resubmit the near-final protocol before activating the IND.
How should investors frame expectations for the April 2 R&D Day and what level of detail will you provide?
The agenda is still being finalized, but the focus will be on praliciguat and AKB-097, with external KOLs (not just Akebia employees) speaking to the excitement around the next-generation complement inhibitor, plus depth on the preclinical data underlying the FSGS decision. Akebia will also introduce AKB-9090, its first internally discovered product entering the clinic. The goal is to let investors, who have rightly focused on the Vafseo launch, understand the newly introduced rare kidney pipeline and the expanding HIF capabilities.