Vitamin D pathway gene polymorphisms as predictors of hepatitis C virus-related mixed cryoglobulinemia

Vitamin D levels in patients with small and medium vessel vasculitis

OBJECTIVES

To determine the prevalence of vitamin D deficiency in patients with small and medium vessel systemic vasculitis.

METHODS

In this cross-sectional study, 25-hydroxy (OH) vitamin D3 levels were measured in adult patients with systemic small and medium vessel vasculitis including antineutrophil cytoplasmic antibody-associated vasculitis (AAV), cryoglobulinaemic vasculitis (CryV), IgA vasculitis (IgAV) and polyarteritis nodosa (PAN), and age- and sex-matched healthy subjects (HS) and patients with rheumatoid arthritis (RA) as control groups. 25OH vitamin D3 levels<30ng/ml and <20ng/ml were regarded as insufficiency and deficiency, respectively.

RESULTS

Fifty-seven patients (42 AAV, 2 CryV, 8 IgA vasculitis, 5 PAN) with systemic vasculitis, 101 HS, and 111 RA patients were included. The mean 25OH vitamin D3 level was 21.8±14.2ng/mL in patients with vasculitis, 42.7±27.6ng/mL in HS (p<.001) and 20.1±18.47ng/mL in patients with RA (p=.54). Vitamin D insufficiency and deficiency were significantly higher in patients with systemic vasculitis compared to HS (75.4% vs 33.7%, p<.001; %50 vs 21.8%, p<.001, respectively). Vitamin D status was not different in patients with systemic vasculitis compared to RA. There was a negative correlation between vitamin D status and CRP levels (=-.364, p=.007). The multivariate logistic regression analysis showed that renal involvement was significantly associated with vitamin D deficiency/insufficiency in patients with vasculitis (OR 22.5 [95% CI 1.6-128.9].

CONCLUSION

Vitamin D deficiency and insufficiency are more frequent in patients with systemic small and medium vessel vasculitis and RA than HS. Renal involvement is one of the factors associated with vitamin D deficiency/insufficiency in patients with vasculitis.

Vitamin D as Modulator of Drug Concentrations: A Study on Two Italian Cohorts of People Living with HIV Administered with Efavirenz

To date, vitamin D seems to have a significant role in affecting the prevention and immunomodulation in COVID-19 disease. Nevertheless, it is important to highlight that this pro-hormone has other several activities, such as affecting drug concentrations, since it regulates the expression of cytochrome P450 (CYP) genes. Efavirenz (EFV) pharmacokinetics is influenced by CYPs, but no data are available in the literature concerning the association among vitamin D levels, seasonality (which affects vitamin D concentrations) and EFV plasma levels. For this reason, the aim of this study was to evaluate the effect of 25-hydroxy vitamin D (25(OH)D3) levels on EFV plasma concentrations in different seasons. We quantified 25(OH)D3 by using chemiluminescence immunoassay, whereas EFV plasma concentrations were quantified with the HPLC–PDA method. A total of 316 patients were enrolled in Turin and Rome. Overall, 25(OH)D3levels resulted in being inversely correlated with EFV concentrations. Some patients with EFV levels higher than 4000 ng/mL showed a deficient 25(OH)D3 concentration in Turin and Rome cohorts and together. EFV concentrations were different in patients without vitamin D supplementation, whereas, for vitamin D-administered individuals, no difference in EFV exposure was present. Concerning seasonality, EFV concentrations were associated with 25(OH)D3 deficiency only in winter and in spring, whereas a significant influence was highlighted for 25(OH)D3 stratification for deficient, insufficient and sufficient values in winter, spring and summer. A strong and inverse association between 25(OH)D3and EFV plasma concentrations was suggested. These data suggest that vitamin D is able to affect drug exposure in different seasons; thus, the achievement of the clinical outcome could be improved by also considering this pro-hormone.

Vitamin D Levels in Patients With Small and Medium Vessel Vasculitis

OBJECTIVES

To determine the prevalence of vitamin D deficiency in patients with small and medium vessel systemic vasculitis.

METHODS

In this cross-sectional study, 25-hydroxy (OH) vitamin D3 levels were measured in adult patients with systemic small and medium vessel vasculitis including antineutrophil cytoplasmic antibody-associated vasculitis (AAV), cryoglobulinaemic vasculitis (CryV), IgA vasculitis (IgAV) and polyarteritis nodosa (PAN), and age- and sex-matched healthy subjects (HS) and patients with rheumatoid arthritis (RA) as control groups. 25OH vitamin D3 levels<30ng/ml and <20ng/ml were regarded as insufficiency and deficiency, respectively.

RESULTS

Fifty-seven patients (42 AAV, 2 CryV, 8 IgA vasculitis, 5 PAN) with systemic vasculitis, 101 HS, and 111 RA patients were included. The mean 25OH vitamin D3 level was 21.8±14.2ng/mL in patients with vasculitis, 42.7±27.6ng/mL in HS (p<.001) and 20.1±18.47ng/mL in patients with RA (p=.54). Vitamin D insufficiency and deficiency were significantly higher in patients with systemic vasculitis compared to HS (75.4% vs 33.7%, p<.001; %50 vs 21.8%, p<.001, respectively). Vitamin D status was not different in patients with systemic vasculitis compared to RA. There was a negative correlation between vitamin D status and CRP levels (=-.364, p=.007). The multivariate logistic regression analysis showed that renal involvement was significantly associated with vitamin D deficiency/insufficiency in patients with vasculitis (OR 22.5 [95% CI 1.6-128.9].

CONCLUSION

Vitamin D deficiency and insufficiency are more frequent in patients with systemic small and medium vessel vasculitis and RA than HS. Renal involvement is one of the factors associated with vitamin D deficiency/insufficiency in patients with vasculitis.

Pharmacogenetics of the anti-HCV drug sofosbuvir: a preliminary study

Background

Sofosbuvir is a potent nucleotide HCV NS5B polymerase inhibitor that is also a P-glycoprotein (encoded by the ABCB1 gene) and breast cancer resistance protein (encoded by the ABCG2 gene) substrate. Concerning previous anti-HCV therapies, pharmacogenetics had a significant impact, particularly considering the association of interleukin28B polymorphisms with dual-therapy (ribavirin + pegylated IFN) outcomes.

Objectives

In this work, we investigated the association between sofosbuvir and its prevalent metabolite (GS-331007) plasma concentrations at 1 month of therapy and genetic variants (SNPs) in genes encoding transporters and nuclear factors (ABCB1, ABCG2 and HNF4α) related to sofosbuvir transport.

Patients and methods

Allelic discrimination was performed through real-time PCR, whereas plasma concentrations were evaluated through liquid chromatography. One hundred and thirteen patients were enrolled.

Results

Sofosbuvir concentrations were below the limit of quantification since the drug was converted into its GS-331007 metabolite. ABCB1 2677 G>T (P = 0.044) and HNF4α 975 C>G (P = 0.049) SNPs were associated with GS-331007 metabolite plasma concentrations. In linear multivariate analysis, liver stiffness, insulin resistance, baseline haemoglobin and haematocrit and SNPs in the ABCB1 gene (3435 CT/TT and 1236 TT genotypes) were significant predictors of GS-331007 concentrations. Furthermore, we performed sub-analyses considering the anti-HCV concomitant drug and HCV genotype, identifying specific polymorphisms associated with GS-331007 plasma concentrations: ABCB1 3435 C>T and HNF4α975 C>G in patients treated with daclatasvir, ABCB1 2677 G>T with ledipasvir and ABCB1 3435 C>T, ABCB1 2677 G>T, ABCG2 421 C>A and ABCG2 1194 + 928 C>A with ribavirin.

Conclusions

In this study we suggested sofosbuvir GS-331007 metabolite plasma levels were affected by variants in the ABCB1 and HNFα genes.

VDR rs7975232/ApaI genetic variation predicts sustained HBsAg loss in HBeAg-positive chronic hepatitis B patients treated with pegylated interferon

AIM

To evaluate the predictive value of vitamin D and its metabolic pathway gene polymorphisms in response to pegylated interferon (Peg-IFN) in hepatitis B early antigen (HBeAg)-positive chronic hepatitis B (CHB) patients.

METHODS

One hundred and nineteen HBeAg-positive CHB patients who received Peg-IFN monotherapy for 48 weeks and then were followed-up for another 48 weeks were prospectively enrolled; baseline 25-hydroxy vitamin D (25-(OH)D) and hepatitis B virus serologic marker levels were detected, nine critical single nucleotide polymorphisms within vitamin D metabolism were genotyped.

RESULTS

Forty-five (37.8%), 44 (37.0%), 35 (29.4%), and 11 (9.2%) of the patients achieved virological response (VR), HBeAg loss, combined response (CR), and hepatitis B surface antigen (HBsAg) level < 200 IU/mL at the end of treatment (EOT; week 48), respectively; 42 (35.3%) and six (5.0%) people achieved HBeAg and HBsAg loss at the end of follow-up (EOF; week 96). Baseline HBeAg level was independent predictor of VR (odds ratio [OR], 0.470; 95% confidence interval [CI], 0.294-0.751; P = 0.002), HBeAg loss (OR, 0.395; 95% CI, 0.243-0.643; P < 0.001), CR (OR, 0.392; 95% CI, 0.215-0.714; P = 0.002) at EOT and HBeAg loss at EOF (OR, 0.334; 95% CI, 0.203-0.559; P < 0.001); baseline HBsAg level itself was independent predictor of both HBsAg < 200 IU/mL at EOT (OR, 0.257; 95% CI, 0.103-0.642; P = 0.004) and HBsAg loss at EOF (OR, 0.232; 95% CI, 0.077-0.702; P = 0.010). Age was also independent predictors of HBsAg loss at EOF (OR, 0.775; 95% CI, 0.634-0.948; P = 0.013). Concerning genetic variation of VDR rs7975232/ ApaI, A allele was the genetic independent predictor of VR at EOT (OR, 1.824; 95% CI, 1.024-3.248; P = 0.041) and HBsAg loss at EOF (OR, 3.566; 95% CI, 1.057-12.029; P = 0.040).

CONCLUSIONS

Genetic variation of VDR rs7975232/ ApaI is a pretreatment predictor of sustained HBsAg loss in HBeAg-positive CHB patients with Peg-IFN monotherapy.

Influence of ABCB11 and HNF4α genes on daclatasvir plasma concentration: preliminary pharmacogenetic data from the Kineti-C study

Background

Daclatasvir is an inhibitor of HCV non-structural 5A protein and is a P-glycoprotein substrate. Pharmacogenetics has had a great impact on previous anti-HCV therapies, particularly considering the association of IL-28B polymorphisms with dual therapy outcome.

Objectives

We investigated the association between daclatasvir plasma concentrations at 2 weeks and 1 month of therapy and genetic variants (SNPs) in genes encoding transporters and nuclear factors (ABCB1, ABCB11 and HNF4α).

Patients and methods

Allelic discrimination was achieved through real-time PCR, whereas plasma concentrations were evaluated through LC-MS/MS.

Results

Fifty-two patients were analysed, all enrolled in the Kineti-C study. HNF4α 975 C > G polymorphism was found to be associated with the daclatasvir plasma concentrations at 2 weeks (P = 0.009) and 1 month of therapy (P = 0.006). Linear regression analysis suggested that, at 2 weeks of therapy, age, baseline BMI and haematocrit were significant predictors of daclatasvir concentrations, whereas at 1 month of therapy ABCB111131 CC and HNF4α CG/GG genotypes were significant predictors of daclatasvir concentrations.

Conclusions

These are the first and preliminary results from our clinical study focusing on daclatasvir pharmacogenetics, showing that this approach could have a role in the era of new anti-HCV therapies.

Vitamin D pathway gene polymorphisms affecting daclatasvir plasma concentration at 2 weeks and 1 month of therapy

AIM

Vitamin D (VD) influences genetic expression through its receptor (VDR). VD pathway gene polymorphisms seem to influence antiviral drug pharmacokinetics and therapeutic outcome/toxicity. We investigated the association between daclatasvir (DCV) plasma concentrations and genetic variants (SNPs) associated with the VD pathway.

PATIENTS & METHODS

Chronic hepatitis C patients treated with DCV from 2014 to 2016 were included. Genotypes were assessed through real-time PCR and plasma concentrations through liquid chromatography.

RESULTS

A total of 52 patients were analyzed. DCV levels were influenced by CYP24A1 rs2248359T>C polymorphism at 2 weeks and VDR Cdx2 A>G at 1 month of treatment. Linear regression analysis showed baseline BMI, alanine aminotransferase and hematocrit as significant predictors of DCV concentrations at 2 weeks, BMI and hematocrit at baseline, VDR Cdx2 AG/GG and FokI TC/CC at 1 month.

CONCLUSION

These results showed a possible role of VD pathway gene polymorphisms in influencing DCV plasma concentrations, but further studies are required.

Vitamin D pathway genetic variants are able to influence sofosbuvir and its main metabolite pharmacokinetics in HCV mono-infected patients

Vitamin D levels and genetic variants were associated with drug outcome/toxicity and concentrations. The plasma exposure of GS-331007, the main sofosbuvir metabolite, has been related to SVR. We evaluated the impact of polymorphisms in genes (CYP27B1, CYP24A1, VDBP and VDR) related to vitamin D pathway on sofosbuvir and GS-331007 plasma levels in HCV mono-infected patients at one month of treatment. Polymorphisms were investigated through real-time PCR; drug plasma quantification was performed through a UHPLC-MS/MS method. GS-331007 levels were associated with CYP24A1rs2248359 and VDRCdx2 variants in all the analyzed patients and linear regression analysis showed that sex, body mass index, HCV genotype, baseline estimated glomerular filtration rate, VDRCdx2AG/GG and CYP27B1-1260TT genotypes significantly predict concentrations. We performed sub-analyses considering the HCV genotype and the concomitant drug, identifying polymorphisms associated with GS-331007 concentrations. This is the first study focusing on vitamin D pathway gene variants and DAAs concentrations, but further studies are required.

Vitamin D pathway gene polymorphisms and hepatocellular carcinoma in chronic hepatitis C-affected patients treated with new drugs

PURPOSE

Since HCV infection may lead to hepatocellular carcinoma (HCC) and vitamin D (deficiency) is related to cancer, we investigated if SNPs in genes involved in vitamin D pathway could predict HCV-related HCC presence in patients treated with new anti-HCV drugs.

METHODS

Patients with chronic hepatitis C and treated with direct-acting antivirals were enrolled. SNPs in VDR, CYP27B1, CYP24A1 and GC genes were assessed through real-time PCR. 258 patients were analyzed.

RESULTS

HCC was present in six patients, all taking sofosbuvir, all males and five/six had cirrhosis. HCV-RNA log levels at baseline were statistically different between patients with and without HCC. VDR FokI T > C SNP resulted associated with HCC: all the CC patients were free from HCC. An association between HCC presence and undetectable HCV-RNA at 1 month of therapy was suggested; cirrhosis was related to HCC. HCC risk factors were age, ribavirin administration, IL28Brs12979860CC and previous treatments; VDR FokICC, sex and insulin resistance were protective factors.

CONCLUSIONS

These data highlighted vitamin D pathway gene SNPs and HCC relationship in the Italian population; further studies are required.

Circannual variation of mitotane and its metabolites plasma levels in patients with adrenocortical carcinoma

OBJECTIVES

Mitotane is the reference drug for the adrenocortical carcinoma treatment; its pharmacological activity seems to depend on drug transformation in two active metabolites: o,p'-DDE (dichlorodiphenylethene) and o,p'-DDA (dichlorodiphenylacetate). Mitotane and metabolites are lipophilic agents; thus, they tend to accumulate into adipose tissues (white and brown), which change their prevalence seasonally. Aim of the work was to evaluate mitotane and metabolites plasma levels variation over the year, in adrenocortical cancer patients treated with Lysodren^® for at least 6 months.

METHODS

We enrolled a group of 86 adrenocortical carcinoma diagnosed patients, who underwent radical surgery and started mitotane as adjuvant treatment. For drug and metabolites plasma level (from samples collected ~12 h after the dose administration of mitotane, just before the subsequent administration) determination, a validated chromatographic method was used.

KEY FINDINGS

Results showed an evidence of a seasonal trend for the three substance (o,p'-DDD, o,p'-DDE and o,p'-DDA) plasma levels, in terms of acrophases and lower values. Furthermore, it came out that male patients need a higher significant mitotane drug dose than female patients to reach mitotane therapeutic window.

CONCLUSIONS

In conclusion, this is the first study assessing a mitotane plasma level variation over the year, but further studies in larger cohorts are required.