Long-term results: APHENITY extension
APHENITY extension study: Effects on diet in PKU
Following the APHENITY clinical trial, this extension study looked at the long-term safety and potential benefits of SEPHIENCE. The goal was to see if SEPHIENCE could help people eat more natural protein while keeping their blood Phe levels in a healthy range.
Who took part?
As of the cutoff date of September 2, 2024, a total of 169 people with PKU joined this study. Participants ranged in age from about 2 months to 55 years old, with a median age of 14. Some people had taken part in the original APHENITY trial, while others were new to SEPHIENCE. This study is still in progress, and the results shown are based on the data collected up to the cutoff date.
How did the study work?
Everyone took SEPHIENCE once a day for at least one year. Participants were grouped based on their blood Phe levels at the start of the study:
- Participants with blood Phe levels lower than 360 µmol/L or 6 mg/dL (n=102) entered a guided dietary Phe tolerance assessment period, during which healthcare providers gradually increased the amount of natural protein they could eat and adjusted their diet every 2 weeks over 26 weeks.
- Participants with blood Phe levels at or greater than 360 µmol/L or 6 mg/dL (n=49) continued taking SEPHIENCE, with no changes made to their diet. All participants had regular check-ins throughout the study.
With SEPHIENCE, many people were able to eat more natural protein
After 26 weeks of treatment, researchers examined changes in the amount of natural protein participants in the dietary assessment group were able to consume relative to their baseline.
Here’s what they found:
97%
(99/102)
Increased their dietary Phe intake
With SEPHIENCE, nearly all participants could relax their diet and increase Phe intake during the 26-week assessment period.
70%
(57/81)
Two out of three participants met their age-adjusted natural protein needs while on SEPHIENCE.
About 60 grams of natural protein per day. After 26 weeks of treatment with SEPHIENCE, a person weighing 110 pounds could consume approximately 60 grams of natural protein per day, based on their dietary Phe tolerance.
Individual results may vary. This information is based on clinical trial data but is not included in the approved full Prescribing Information for SEPHIENCE. Talk to your healthcare provider if you have any questions.
A real-life moment of flexibility
For Thomas, introducing more protein into his diet meant being able to connect with family traditions in a new way.
“
I made arroz con habichuelas for the first time… And I gave some to my mother to try, and she said that it was just like what her grandmother used to make.
-Thomas
APHENITY extension study: Long-term safety was consistent with the APHENITY trial
- In the ongoing extension study, 169 people took SEPHIENCE for up to 2.6 years
- The most common side effects (seen in 2% or more of participants) were headache, diarrhea, unusual-colored feces, vomiting, and tiredness
- No new safety concerns were seen. The safety profile of SEPHIENCE remained consistent throughout the extension study
These are not all the possible side effects of SEPHIENCE. If you experience any side effects,
tell your healthcare provider.
Additional study details
From the APHENITY Extension Study
Objective: To evaluate the long-term safety and effectiveness of SEPHIENCE in people with PKU and to see if it helped them eat more natural protein while keeping their blood Phe levels in a healthy range.
Method: Participants included people who completed the original APHENITY trial as well as new participants with either lower (below 360 μmol/L; n=102) or higher than (360 μmol/L; n=49) blood Phe levels at the start of the extension study. All participants took SEPHIENCE once daily for at least one year. Those who had lower blood Phe levels joined a 26-week assessment period, where healthcare providers slowly increased the amount of protein they could eat, adjusting the diet every two weeks. Those with higher Phe levels continued treatment without changes to their diet, but all participants had regular check-ins throughout the study. The primary focus was on long-term safety and changes in how much Phe or protein participants could eat from the beginning of the study to Week 26.
Results: A total of 169 participants, ranging in age from ~2 months to 55 years (with a median age of 14 years), were included. Most participants in the dietary assessment group—97%—were able to increase the amount of dietary Phe consumed at some point during the study. 70% of participants met the recommended daily amount of protein for their age. 73% of participants were able to double their starting Phe intake, and 34% were able to triple it. Safety results remained consistent with the APHENITY trial. The most common side effects were headache, diarrhea, unusual-colored feces, vomiting, and tiredness; no serious side effects or deaths were reported.
PLEASE NOTE: Individual results may vary. This information is based on clinical trial data but is not included in the approved full Prescribing Information for SEPHIENCE. Talk to your healthcare provider if you have any questions.
