This is fantastic news. After 20 years and more in gestation, the Lectura romana of St Thomas—also known as (but wrongly) the "Alia lectura"—has been published. Fred Unwalla, of the Pontifical Institute of Mediaeval Studies’s Publications Department, sent me this yesterday:
The Pontifical Institute of Mediaeval Studies is proud to announce the publication of a previously lost work of Thomas Aquinas: the Lectura romana in primum Sententiarum Petri Lombardi, edited by † Leonard E. Boyle, OP and John F. Boyle.
Ptolomeo of Lucca, the friend, confessor, and biographer of Aquinas, uniquely reported that Thomas, while in Rome, had written a second commentary on Book I of Peter Lombard’s Liber sententiarum. The Lectura romana is that commentary. It is a reportatio of Aquinas’ lectures on Peter Lombard given in Rome in 1265–1266. 
An entirely new commentary, the Lectura romana contains a prolog, ninety-seven articles covering distinctions 1–17 and 23, and three short notes on distinctions 3 and 24. These lectures cover the nature of sacra doctrina, the names and attributes of God, the Trinity, and charity.
The Roman Province of the Order of Preachers had established a new studium at Rome in which Thomas would teach his fellow Dominicans beginning their theological education. The Lectura romana constituted part of his teaching in this new studium. In this work, we have the only surviving reportatio of Thomas’ teaching other than biblical commentaries. Written with the trim precision of the Summa theologiae, the Lectura romana contains questions, arguments, and examples not found elsewhere in the works of Aquinas. Because it can be precisely dated to 1265–1266, it is also particularly promising for understanding the development of Aquinas’ thought on a number of central theological topics.
The Lectura romana survives in the margins and guard folia of a thirteenth-century manuscript of the Parisian Scriptum now in Lincoln College, Oxford.
Orders from within North America may be sent to the Department of Publications. Further information about ordering, a complete description, and an excerpt from the book, are available online at www.pims.ca. The book will be distributed in Europe by Brepols Publishers later this spring.
And when you do go to the PIMS web site, You’ll find a downloadable PDF file with the Preface and the contents of the Lectura romana. I plan to discuss this volume—and the larger topic of this Lectura—in my upcoming Newsletter. Fantastic news.
PS: While you are there at the PIMS web site, notice the publication in English of Raymond of Penyafort’s Summa on marriage, translated by Pierre J. Payer; at the end of that volume Payer has a table the assembles the parallels between Raymond’s account of marriage in his Summa and that of Aquinas in his Scriptum on the Sentences (which is the single fullest treatment available to us, as Thomas did not get to the treatise on marriage in the Tertia pars).
