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We present radial velocity measurements of the very bright ($V\sim5.7$) nearby F star, DMPP-4 (HD 184960). The anomalously low Ca II H&K emission suggests mass loss from planets orbiting a low activity host star. Periodic radial velocity variability with $\sim 10$ ms$^{-1}$ amplitude is found to persist over a $>4$ year timescale. Although the non-simultaneous photometric variability in four TESS sectors supports the view of an inactive star, we identify periodic photometric signals and also find spectroscopic evidence for stellar activity. We used a posterior sampling algorithm that includes the number of Keplerian signals, $N_\textrm{p}$, as a free parameter to test and compare (1) purely Keplerian models (2) a Keplerian model with linear activity correlation and (3) Keplerian models with Gaussian processes. A preferred model, with one Keplerian and quasi-periodic Gaussian process indicates a planet with a period of $P_\textrm{b} = 3.4982^{+0.0015}_{-0.0027}$ d and corresponding minimum mass of $m_\textrm{b}\,\textrm{sin}\,i = 12.2^{+1.8}_{-1.9}$ M$_\oplus$. Without further high time resolution observations over a longer timescale, we cannot definitively rule out the purely Keplerian model with 2 candidates planets with $P_\textrm{b} = 2.4570^{+0.0026}_{-0.0462}$ d, minimum mass $m_\textrm{b}\,\textrm{sin}\,i = 8.0^{+1.1}_{-1.5}$ M$_\oplus$ and $P_\textrm{c} = 5.4196^{+0.6766}_{-0.0030}$ d and corresponding minimum mass of $m_\textrm{b}\,\textrm{sin}\,i = 12.2^{+1.4}_{-1.6}$ M$_\oplus$. The candidate planets lie in the region below the lower-envelope of the Neptune Desert. Continued mass loss may originate from the highly irradiated planets or from an as yet undetected body in the system., Comment: 19 pages, 11 figures. Accepted for publication in MNRAS

We present radial velocity measurements of the very bright (V ∼ 5.7) nearby F star, DMPP-4 (HD 184960). The anomalously low Ca II H&K emission suggests mass-loss from planets orbiting a low activity host star. Periodic radial velocity variability with ∼10 m s−1 amplitude is found to persist over a >4 yr time-scale. Although the non-simultaneous photometric variability in four TESS sectors supports the view of an inactive star, we identify periodic photometric signals and also find spectroscopic evidence for stellar activity. We used a posterior sampling algorithm that includes the number of Keplerian signals, Np, as a free parameter to test and compare (1) purely Keplerian models (2) a Keplerian model with linear activity correlation and (3) Keplerian models with Gaussian processes. A preferred model, with one Keplerian and quasi-periodic Gaussian process indicates a planet with a period of Pb = 3.4982+0.0015 −0.0027 d and corresponding minimum mass of mb sin i = 12.2+1.8 −1.9 M⊕. Without further high-time resolution observations over a longer time-scale, we cannot definitively rule out the purely Keplerian model with two candidates planets with Pb = 2.4570+0.0026 −0.0462 d, minimum mass mb sin i = 8.0+1.1 −1.5 M⊕ and Pc = 5.4196+0.6766 −0.0030 d and corresponding minimum mass of mb sin i = 12.2+1.4 −1.6 M⊕. The candidate planets lie in the region below the lower-envelope of the Neptune Desert. Continued mass-loss may originate from the highly irradiated planets or from an as yet undetected body in the system.

NI-0801 is a fully human monoclonal antibody against chemokine (C-X-C motif) ligand 10 (CXCL10), which is involved in the recruitment of inflammatory T cells into the liver. The safety and efficacy of NI-0801 was assessed in patients with primary biliary cholangitis. In this open-label phase 2a study, patients with primary biliary cholangitis with an inadequate response to ursodeoxycholic acid received six consecutive intravenous administrations of NI-0801 (10 mg/kg) every 2 weeks. Patients were followed up for 3 months after the last infusion. Liver function tests, safety assessments, as well as pharmacokinetic and pharmacodynamic parameters were evaluated at different time points throughout the dosing period and the safety follow-up period. Twenty-nine patients were enrolled in the study and were treated with NI-0801. The most frequently reported adverse events included headaches (52%), pruritus (34%), fatigue (24%), and diarrhea (21%). No study drug-related serious adverse events were reported. NI-0801 administration did not lead to a significant reduction in any of the liver function tests assessed at the end of the treatment period (i.e., 2 weeks after final NI-0801 administration) compared to baseline. Conclusion: Despite clear pharmacologic responses in the blood, no therapeutic benefit of multiple administrations of NI-0801 could be demonstrated. The high production rate of CXCL10 makes it difficult to achieve drug levels that lead to sustained neutralization of the chemokine, thus limiting its targetability.

We present radial velocity measurements of the very bright (V ∼ 5.7) nearby F star, DMPP-4 (HD 184960). The anomalously low Ca ii H&K emission suggests mass loss from planets orbiting a low activity host star. Periodic radial velocity variability with ∼10 m s−1 amplitude is found to persist over a > 4 year timescale. Although the non-simultaneous photometric variability in four TESS sectors supports the view of an inactive star, we identify periodic photometric signals and also find spectroscopic evidence for stellar activity. We used a posterior sampling algorithm that includes the number of Keplerian signals, Np, as a free parameter to test and compare (1) purely Keplerian models (2) a Keplerian model with linear activity correlation and (3) Keplerian models with Gaussian processes. A preferred model, with one Keplerian and quasi-periodic Gaussian process indicates a planet with a period of $P_\textrm {b} = 3.4982^{+0.0015}_{-0.0027}$ d and corresponding minimum mass of $m_\textrm {b}\, \textrm {sin}\, i = 12.2^{+1.8}_{-1.9}$ M⊕. Without further high time resolution observations over a longer timescale, we cannot definitively rule out the purely Keplerian model with 2 candidates planets with $P_\textrm {b} = 2.4570^{+0.0026}_{-0.0462}$ d, minimum mass $m_\textrm {b}\, \textrm {sin}\, i = 8.0^{+1.1}_{-1.5}$ M⊕ and $P_\textrm {c} = 5.4196^{+0.6766}_{-0.0030}$ d and corresponding minimum mass of $m_\textrm {b}\, \textrm {sin}\, i = 12.2^{+1.4}_{-1.6}$ M⊕. The candidate planets lie in the region below the lower-envelope of the Neptune Desert. Continued mass loss may originate from the highly irradiated planets or from an as yet undetected body in the system.