In patients with chronic hepatitis B with impaired renal function, renal safety is good after switching to TAF. Research Express

Introduction Long-term use of nucleotide analogues [such as adefovir dipivoxil (ADV) or tenofovir disoproxil fumarate (TDF)] may cause renal damage and bone density reduction.
Therefore, patients need to use less toxic Of antiviral drugs
.

Tenofovir fumarate (TAF) is a prodrug of tenofovir.
Compared with TDF, TAF uses a small dose, is selectively delivered into cells, and is more stable in plasma, ensuring its high At the same time of antiviral activity, it significantly reduces bone and nephrotoxicity
.

Recently, Hosaka and other scholars conducted a prospective observational cohort study to evaluate the longitudinal changes in renal function and biochemical indicators in patients with chronic hepatitis B (CHB) within 2 years after switching from long-term ADV and TDF to TAF, and to explore Factors related to the improvement of renal function in patients after switching to TAF
.

Research methods included 306 patients with CHB who converted from long-term TDF or ADV to TAF
.

The baseline date (day 0) is defined as the date when the switch to TAF begins
.

The main outcome is to estimate the change in glomerular filtration rate (eGFR) after switching to TAF
.

The results of the study were that the median eGFR of 306 patients at baseline was 64.
4 mL/min/1.
73 m2 (IQR: 56.
7-74.
0).
Among them, 200 patients (65.
3%) and 106 patients (34.
7%) were affected at baseline, respectively.
There are stage 1-2 and stage 3a-4 chronic kidney disease (CKD), that is, there are 16 cases, 184 cases, 94 cases, 11 cases and 1 patient with baseline eGFR≥90 (CKD stage 1), 60≤eGFR< 90 (stage 2), 45≤eGFR＜60 (stage 3a), 30≤eGFR＜45 (stage 3b) and 15≤eGFR＜30 (stage 4) (Table 1)
.

Table 1 Baseline characteristics of patients After switching to TAF, the average eGFR of CKD 3a-4 patients increased significantly until the 12th week, and remained stable from the 12th week to the 2nd year (using the linear mixed-effects model to correct the slope: +9.
01 mL/min/1.
73 m2/year, until the 12th week; P<0.
001)
.

In contrast, the average eGFR of CKD stage 1-2 patients remained stable from baseline to year 2 (Table 2)
.

Table 2 Multivariate logistic regression analysis of eGFR slope changes after the start of TAF treatment showed that the baseline CKD stage ≥3a, the greater decline in eGFR 1 year before switching to TAF, and the shorter use time of any nucleotide analogs and the improvement of eGFR in the first year ≥10% is significantly correlated
.

The study concluded that switching from TDF or ADV to TAF for 2 years of renal safety is good
.

In CKD stage 3a-4 patients, eGFR increased during the first 12 weeks after switching to TAF, and then remained stable
.

References: [1] Hosaka T, Suzuki F, Kobayashi M, et al.
Renal safety and biochemical changes for two years of tenofovir alafenamide after switching from long-term other nucleotide analogues treatment in patients with chronic hepatitis B[J].
Hepatol Res.
2021 Oct 22.
doi: 10.
1111/hepr.
13726.
[2] Viral Hepatitis Group, Hepatology Branch of Chinese Research Hospital Association.
Expert consensus on diagnosis and treatment of chronic hepatitis B with persistent normal alanine aminotransferase.
Chinese study Type Hospital.
2021.
8(4):1-6.